CVE-2026-99999
CRITICAL 9.3 PoC CATALOGUEDIn the Linux kernel, the following vulnerability has been resolved: ipv4: validate checksum_start before completing checksum If a packet with bad checksum metadata gets into the ipv4 stack, skb_checksum_help can corrupt the network header and cause a bunch of mischief. This was discovered and reported by Paulos, and has been reporoduced by others independently since. We really shouldn't allow such packets in, but as a defence in depth measure, let's also check before we complete the checksum. A more complete validation at input is forthcoming, but needs more work.
VulnCheck KEV reports exploitation for this CVE. These are source-specific reports; review the details and vendor guidance below.
Exploitation likelihood
0.8%chance of exploitation in 30 days · 56th percentile
Impact if exploited
9.3CVSS 3.1 · CRITICAL
- ConfidentialityHigh
- IntegrityHigh
- AvailabilityHigh
What an attacker needs
- ⚠Access: Requires local access to the host
- ✓Privileges: No account or privileges required
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept
Public PoC or exploit resources are catalogued below.
- VulnCheck KEV · XDB d78be1b0f067 · Linked repository
- VulnCheck KEV · XDB 319a7fb4465f · Linked repository
Listed by the named source; Vulnpedia has not tested these resources.
PoC data: JSON
Resource commands
curl -s https://vulnpedia.com/cve/CVE-2026-99999/poc.jsonMachine-readable PoC index for this CVE (for automation).Search for new PoCs
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Data snapshot:
Weakness (CWE)
- CWE-20: Improper Input Validation
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
References and research data (JSON)
Vendor product assessments
Showing 32 of 2187 vendor product statements; 2155 omitted. Read the full vendor advisory.
kernel-0:6.12.0-265.29.el10nv.aarch64 as a component of NVIDIA for RHEL 10 · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]?arch=aarch64
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. Red Hat recommends treating all kernel errata as security-relevant. Given the kernel's fundamental role, any bug has a higher chance of impacting system security, even if that impact only becomes clear after a fix is published. Therefore, Red Hat prioritizes delivering fixes that improve our customers' overall security posture. Because of this proactive approach, a patch may be associated with a CVE assignment at a future date. Retroactive CVE assignments are always documented in the corresponding errata and on Red Hat's CVE pages. We strongly advise against delaying updates, as doing so may leave your system exposed when protections are already available. Vendor guidance
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
kernel-debuginfo-0:3.10.0-1160.167.2.el7.x86_64 as a component of Red Hat Enterprise Linux Server Optional (v. 7 ELS) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]?arch=x86_64
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. Red Hat recommends treating all kernel errata as security-relevant. Given the kernel's fundamental role, any bug has a higher chance of impacting system security, even if that impact only becomes clear after a fix is published. Therefore, Red Hat prioritizes delivering fixes that improve our customers' overall security posture. Because of this proactive approach, a patch may be associated with a CVE assignment at a future date. Retroactive CVE assignments are always documented in the corresponding errata and on Red Hat's CVE pages. We strongly advise against delaying updates, as doing so may leave your system exposed when protections are already available. Vendor guidance
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
libperf-debuginfo-0:6.12.0-211.67.1.el10_2.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 10) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_2?arch=x86_64
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. Red Hat recommends treating all kernel errata as security-relevant. Given the kernel's fundamental role, any bug has a higher chance of impacting system security, even if that impact only becomes clear after a fix is published. Therefore, Red Hat prioritizes delivering fixes that improve our customers' overall security posture. Because of this proactive approach, a patch may be associated with a CVE assignment at a future date. Retroactive CVE assignments are always documented in the corresponding errata and on Red Hat's CVE pages. We strongly advise against delaying updates, as doing so may leave your system exposed when protections are already available. Vendor guidance
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
perf-0:5.14.0-427.157.1.el9_4.x86_64 as a component of Red Hat Enterprise Linux AppStream E4S (v.9.4) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_4?arch=x86_64
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. Red Hat recommends treating all kernel errata as security-relevant. Given the kernel's fundamental role, any bug has a higher chance of impacting system security, even if that impact only becomes clear after a fix is published. Therefore, Red Hat prioritizes delivering fixes that improve our customers' overall security posture. Because of this proactive approach, a patch may be associated with a CVE assignment at a future date. Retroactive CVE assignments are always documented in the corresponding errata and on Red Hat's CVE pages. We strongly advise against delaying updates, as doing so may leave your system exposed when protections are already available. Vendor guidance
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
libperf-debuginfo-0:5.14.0-687.59.1.el9_8.s390x as a component of Red Hat Enterprise Linux AppStream (v. 9) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_8?arch=s390x
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. Red Hat recommends treating all kernel errata as security-relevant. Given the kernel's fundamental role, any bug has a higher chance of impacting system security, even if that impact only becomes clear after a fix is published. Therefore, Red Hat prioritizes delivering fixes that improve our customers' overall security posture. Because of this proactive approach, a patch may be associated with a CVE assignment at a future date. Retroactive CVE assignments are always documented in the corresponding errata and on Red Hat's CVE pages. We strongly advise against delaying updates, as doing so may leave your system exposed when protections are already available. Vendor guidance
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
kernel-64k-debug-modules-core-0:6.12.0-211.67.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 10) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_2?arch=aarch64
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. Red Hat recommends treating all kernel errata as security-relevant. Given the kernel's fundamental role, any bug has a higher chance of impacting system security, even if that impact only becomes clear after a fix is published. Therefore, Red Hat prioritizes delivering fixes that improve our customers' overall security posture. Because of this proactive approach, a patch may be associated with a CVE assignment at a future date. Retroactive CVE assignments are always documented in the corresponding errata and on Red Hat's CVE pages. We strongly advise against delaying updates, as doing so may leave your system exposed when protections are already available. Vendor guidance
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
kernel-debuginfo-0:4.18.0-553.178.1.el8_10.s390x as a component of Red Hat Enterprise Linux BaseOS (v. 8) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_10?arch=s390x
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. Red Hat recommends treating all kernel errata as security-relevant. Given the kernel's fundamental role, any bug has a higher chance of impacting system security, even if that impact only becomes clear after a fix is published. Therefore, Red Hat prioritizes delivering fixes that improve our customers' overall security posture. Because of this proactive approach, a patch may be associated with a CVE assignment at a future date. Retroactive CVE assignments are always documented in the corresponding errata and on Red Hat's CVE pages. We strongly advise against delaying updates, as doing so may leave your system exposed when protections are already available. Vendor guidance
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
kernel-modules-0:4.18.0-372.224.1.el8_6.x86_64 as a component of Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.6) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_6?arch=x86_64
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. Red Hat recommends treating all kernel errata as security-relevant. Given the kernel's fundamental role, any bug has a higher chance of impacting system security, even if that impact only becomes clear after a fix is published. Therefore, Red Hat prioritizes delivering fixes that improve our customers' overall security posture. Because of this proactive approach, a patch may be associated with a CVE assignment at a future date. Retroactive CVE assignments are always documented in the corresponding errata and on Red Hat's CVE pages. We strongly advise against delaying updates, as doing so may leave your system exposed when protections are already available. Vendor guidance
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
kernel-modules-0:5.14.0-284.199.1.el9_2.aarch64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.9.2) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_2?arch=aarch64
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. Red Hat recommends treating all kernel errata as security-relevant. Given the kernel's fundamental role, any bug has a higher chance of impacting system security, even if that impact only becomes clear after a fix is published. Therefore, Red Hat prioritizes delivering fixes that improve our customers' overall security posture. Because of this proactive approach, a patch may be associated with a CVE assignment at a future date. Retroactive CVE assignments are always documented in the corresponding errata and on Red Hat's CVE pages. We strongly advise against delaying updates, as doing so may leave your system exposed when protections are already available. Vendor guidance
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
perf-debuginfo-0:5.14.0-427.157.1.el9_4.aarch64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.9.4) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_4?arch=aarch64
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. Red Hat recommends treating all kernel errata as security-relevant. Given the kernel's fundamental role, any bug has a higher chance of impacting system security, even if that impact only becomes clear after a fix is published. Therefore, Red Hat prioritizes delivering fixes that improve our customers' overall security posture. Because of this proactive approach, a patch may be associated with a CVE assignment at a future date. Retroactive CVE assignments are always documented in the corresponding errata and on Red Hat's CVE pages. We strongly advise against delaying updates, as doing so may leave your system exposed when protections are already available. Vendor guidance
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
kernel-debug-core-0:5.14.0-687.59.1.el9_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS (v. 9) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_8?arch=ppc64le
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. Red Hat recommends treating all kernel errata as security-relevant. Given the kernel's fundamental role, any bug has a higher chance of impacting system security, even if that impact only becomes clear after a fix is published. Therefore, Red Hat prioritizes delivering fixes that improve our customers' overall security posture. Because of this proactive approach, a patch may be associated with a CVE assignment at a future date. Retroactive CVE assignments are always documented in the corresponding errata and on Red Hat's CVE pages. We strongly advise against delaying updates, as doing so may leave your system exposed when protections are already available. Vendor guidance
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
kernel-tools-debuginfo-0:6.12.0-211.67.1.el10_2.s390x as a component of Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_2?arch=s390x
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. Red Hat recommends treating all kernel errata as security-relevant. Given the kernel's fundamental role, any bug has a higher chance of impacting system security, even if that impact only becomes clear after a fix is published. Therefore, Red Hat prioritizes delivering fixes that improve our customers' overall security posture. Because of this proactive approach, a patch may be associated with a CVE assignment at a future date. Retroactive CVE assignments are always documented in the corresponding errata and on Red Hat's CVE pages. We strongly advise against delaying updates, as doing so may leave your system exposed when protections are already available. Vendor guidance
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
python3-perf-debuginfo-0:6.12.0-211.67.1.el10_2.x86_64 as a component of Red Hat Enterprise Linux Hidden (v. 10) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_2?arch=x86_64
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. Red Hat recommends treating all kernel errata as security-relevant. Given the kernel's fundamental role, any bug has a higher chance of impacting system security, even if that impact only becomes clear after a fix is published. Therefore, Red Hat prioritizes delivering fixes that improve our customers' overall security posture. Because of this proactive approach, a patch may be associated with a CVE assignment at a future date. Retroactive CVE assignments are always documented in the corresponding errata and on Red Hat's CVE pages. We strongly advise against delaying updates, as doing so may leave your system exposed when protections are already available. Vendor guidance
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
libperf-debuginfo-0:5.14.0-687.59.1.el9_8.x86_64 as a component of Red Hat Enterprise Linux Real Time for NFV (v. 9) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_8?arch=x86_64
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. Red Hat recommends treating all kernel errata as security-relevant. Given the kernel's fundamental role, any bug has a higher chance of impacting system security, even if that impact only becomes clear after a fix is published. Therefore, Red Hat prioritizes delivering fixes that improve our customers' overall security posture. Because of this proactive approach, a patch may be associated with a CVE assignment at a future date. Retroactive CVE assignments are always documented in the corresponding errata and on Red Hat's CVE pages. We strongly advise against delaying updates, as doing so may leave your system exposed when protections are already available. Vendor guidance
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
kernel-rt-debuginfo-0:5.14.0-284.199.1.rt14.484.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time E4S (v.9.2) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_2?arch=x86_64
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. Red Hat recommends treating all kernel errata as security-relevant. Given the kernel's fundamental role, any bug has a higher chance of impacting system security, even if that impact only becomes clear after a fix is published. Therefore, Red Hat prioritizes delivering fixes that improve our customers' overall security posture. Because of this proactive approach, a patch may be associated with a CVE assignment at a future date. Retroactive CVE assignments are always documented in the corresponding errata and on Red Hat's CVE pages. We strongly advise against delaying updates, as doing so may leave your system exposed when protections are already available. Vendor guidance
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
python3-perf-debuginfo-0:5.14.0-687.59.1.el9_8.x86_64 as a component of Red Hat Enterprise Linux Real Time (v. 9) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_8?arch=x86_64
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. Red Hat recommends treating all kernel errata as security-relevant. Given the kernel's fundamental role, any bug has a higher chance of impacting system security, even if that impact only becomes clear after a fix is published. Therefore, Red Hat prioritizes delivering fixes that improve our customers' overall security posture. Because of this proactive approach, a patch may be associated with a CVE assignment at a future date. Retroactive CVE assignments are always documented in the corresponding errata and on Red Hat's CVE pages. We strongly advise against delaying updates, as doing so may leave your system exposed when protections are already available. Vendor guidance
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
kernel as a component of Red Hat Enterprise Linux 6 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/kernel
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
- none available: Affected
kernel-bootwrapper as a component of Red Hat Enterprise Linux 6 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/kernel-bootwrapper
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
- none available: Affected
kernel-devel as a component of Red Hat Enterprise Linux 6 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/kernel-devel
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
- none available: Affected
kernel-firmware as a component of Red Hat Enterprise Linux 6 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/kernel-firmware
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
- none available: Affected
kernel-kdump-devel as a component of Red Hat Enterprise Linux 6 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/kernel-kdump-devel
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
- none available: Affected
perf as a component of Red Hat Enterprise Linux 6 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/perf
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
- none available: Affected
kernel-rt-core as a component of Red Hat Enterprise Linux 9 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/kernel-rt-core
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
- none available: Affected
kernel-rt-debug-core as a component of Red Hat Enterprise Linux 9 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/kernel-rt-debug-core
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
- none available: Affected
kernel-rt-debug-kvm as a component of Red Hat Enterprise Linux 9 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/kernel-rt-debug-kvm
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
- none available: Affected
kernel-rt-debug-modules-core as a component of Red Hat Enterprise Linux 9 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/kernel-rt-debug-modules-core
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
- none available: Affected
kernel-rt-debug-modules-partner as a component of Red Hat Enterprise Linux 9 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/kernel-rt-debug-modules-partner
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
- none available: Affected
kernel-rt-devel-matched as a component of Red Hat Enterprise Linux 9 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/kernel-rt-devel-matched
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
- none available: Affected
kernel-rt-modules-core as a component of Red Hat Enterprise Linux 9 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/kernel-rt-modules-core
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
- none available: Affected
kernel-rt-modules-internal as a component of Red Hat Enterprise Linux 9 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/kernel-rt-modules-internal
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
- none available: Affected
kernel-rt.src as a component of Red Hat Enterprise Linux 9 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/kernel-rt?arch=src
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
- none available: Affected
openshift/ose-rhel-coreos-9 as a component of Red Hat OpenShift Container Platform 4 · known affected
Vendor assessment for this product only.
pkg:oci/ose-rhel-coreos-9?repository_url=registry.redhat.io/openshift/ose-rhel-coreos-9
- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
- none available: Affected
Unverified PoC candidates
Catalogue matches for further research. These repositories have not been validated as working exploits.
14 candidates
- https://github.com/MChorfa/csumguard
Restricted eBPF TC ingress guard, CO-RE detector, verified loader, and C11 VMM launch supervisor for CVE-2026-99999
PoC-in-GitHub · CVE-2026-99999
PoC-in-GitHub · CVE-2026-99999 · Updated 2026-10-20T17:48:45Z - https://github.com/PeronGH/CVE-2026-99999
PoC for CVE-2026-99999 (PwnEscape) on a prepared TAP.
PoC-in-GitHub · CVE-2026-99999
PoC-in-GitHub · CVE-2026-99999 · Updated 2026-10-23T03:17:14Z - https://github.com/Quaerendir/cve-2026-99999-audit
cve-2026-99999-audit script (PwnEscape)
PoC-in-GitHub · CVE-2026-99999
PoC-in-GitHub · CVE-2026-99999 · Updated 2026-10-18T21:51:08Z - https://github.com/kingahmadr/CVE-2026-99999-kernel-checkPoC-in-GitHub · CVE-2026-99999
PoC-in-GitHub · CVE-2026-99999 · Updated 2026-10-18T10:07:22Z - https://github.com/nsrg-fmlorg/kpatch-alma-cve-2026-99999
kpatch livepatch build for CVE-2026-99999 on AlmaLinux 8/9 GA kernels
PoC-in-GitHub · CVE-2026-99999
PoC-in-GitHub · CVE-2026-99999 · Updated 2026-10-21T02:47:38Z - https://github.com/01luyicheng/CVE-2026-99999
CVE-2026-99999 PwnEscape PoC - Linux kernel IPv4 csum_start validation bug guest-to-host memory leak (CVSS 9.3)
PoC-in-GitHub · CVE-2026-99999
PoC-in-GitHub · CVE-2026-99999 · Updated 2026-10-21T02:36:09Z - https://github.com/gandli/CVE-2026-99999-pwnescape
CVE-2026-99999 (PwnEscape) reproduction: IPv4 csum_start validation bug — IHL rewrite and 32-byte kernel heap disclosure
PoC-in-GitHub · CVE-2026-99999
PoC-in-GitHub · CVE-2026-99999 · Updated 2026-10-26T07:36:44Z - https://github.com/shizuku198411/CVE-2026-99999-KVM-checksum-metadata-non-destructive-PoCPoC-in-GitHub · CVE-2026-99999
PoC-in-GitHub · CVE-2026-99999 · Updated 2026-10-19T09:45:29Z - https://github.com/nsrg-fmlorg/kpatch-rocky-cve-2026-99999
kpatch livepatch build and load test for CVE-2026-99999 on Rocky Linux 8.10 (4.18.0-553.144.1.el8_10)
PoC-in-GitHub · CVE-2026-99999
PoC-in-GitHub · CVE-2026-99999 · Updated 2026-10-22T01:30:10Z - https://github.com/alvaroguzmancode/CVE-2026-99999PoC-in-GitHub · CVE-2026-99999
PoC-in-GitHub · CVE-2026-99999 · Updated 2026-10-19T15:53:21Z - https://github.com/sqzer-x/cve-2026-99999-scanner
Checks whether a Linux system is affected by CVE-2026-99999 (PwnEscape) and prints or applies the distribution-specific kernel fix
PoC-in-GitHub · CVE-2026-99999
PoC-in-GitHub · CVE-2026-99999 · Updated 2026-10-21T00:07:20Z - https://github.com/01luyicheng/CVE-2026-99999-analysis
CVE-2026-99999 Educational Analysis — attack chain simulation of Linux kernel csum_start bug (CVSS 9.3). See also: CVE-2026-99999-exploit (Working PoC).
PoC-in-GitHub · CVE-2026-99999
PoC-in-GitHub · CVE-2026-99999 · Updated 2026-10-20T09:33:59Z - https://github.com/01luyicheng/CVE-2026-99999-exploit
CVE-2026-99999 Working PoC — real VM escape for Linux kernel csum_start bug (CVSS 9.3). Guest-to-Host heap leak. See also: CVE-2026-99999-analysis (Educational).
PoC-in-GitHub · CVE-2026-99999
PoC-in-GitHub · CVE-2026-99999 · Updated 2026-10-21T11:52:58Z - https://github.com/unixreaper/CVE-2026-99999-ResearchPoC-in-GitHub · CVE-2026-99999
PoC-in-GitHub · CVE-2026-99999 · Updated 2026-10-25T06:27:44Z
Additional exploitation reports
Source-specific reports, separate from CISA KEV. Repeated observations from one source are not independent confirmations.
- VulnCheck KEV · 2026-10-19T00:00:00Z
Source guidance: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Source ransomware assessment: Unknown
VulnCheck KEV · CVE-2026-99999 · Updated 2026-10-19T00:00:00Z - VulnCheck KEV · 2026-10-19T00:00:00ZVulnCheck KEV · CVE-2026-99999
All CVSS metrics
- CRITICAL 9.3 v3.1 · CNA Primary
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - CRITICAL 9.3 v3.1 · NVD Secondary
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
References
Advisories
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-99999.json Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-102044 EUVD · EUVD-2026-102044
- https://vulncheck.com/kev VulnCheck KEV · CVE-2026-99999 · Updated 2026-10-19T00:00:00Z
Technical & other
- https://git.kernel.org/stable/c/a464d950f31c89565cbaae038cc60db04fe01956CVE record · Linux · Updated 2026-10-24T14:17:15.740Z
NVD · CVE-2026-99999 · Updated 2026-10-19T22:17:28.667 - https://git.kernel.org/stable/c/0fab003ef4698e0628060a45a48f14b43ba2a40aCVE record · Linux · Updated 2026-10-24T14:17:15.740Z
NVD · CVE-2026-99999 · Updated 2026-10-19T22:17:28.667 - https://git.kernel.org/stable/c/94524b7b32691de2e2ce162c04d6cbc9106e5cbfCVE record · Linux · Updated 2026-10-24T14:17:15.740Z
NVD · CVE-2026-99999 · Updated 2026-10-19T22:17:28.667 - https://git.kernel.org/stable/c/a65f69e0f38ffbed1b128029e09097436416dc8bCVE record · Linux · Updated 2026-10-24T14:17:15.740Z
NVD · CVE-2026-99999 · Updated 2026-10-19T22:17:28.667 - https://git.kernel.org/stable/c/32a8b0adaa18e52aaa0b246b5ffe683075354dbbCVE record · Linux · Updated 2026-10-24T14:17:15.740Z
NVD · CVE-2026-99999 · Updated 2026-10-19T22:17:28.667 - https://git.kernel.org/stable/c/f3e835af6226f1dd12160cbd696081e9b6155de0CVE record · Linux · Updated 2026-10-24T14:17:15.740Z
NVD · CVE-2026-99999 · Updated 2026-10-19T22:17:28.667 - https://git.kernel.org/stable/c/c3e33464746166264334641dc850a36eef7e6326CVE record · Linux · Updated 2026-10-24T14:17:15.740Z
NVD · CVE-2026-99999 · Updated 2026-10-19T22:17:28.667 - https://git.kernel.org/stable/c/6785011f8b16abf40b1e9d8b2e332232b3e68822CVE record · Linux · Updated 2026-10-24T14:17:15.740Z
NVD · CVE-2026-99999 · Updated 2026-10-19T22:17:28.667 - https://pwn.ai/blog/pwnescapeCVE record · Linux · Updated 2026-10-24T14:17:15.740Z
NVD · CVE-2026-99999 · Updated 2026-10-19T22:17:28.667 - https://vercel.com/blog/findings-from-the-1-million-dollar-vercel-sandbox-challengeCVE record · Linux · Updated 2026-10-24T14:17:15.740Z
NVD · CVE-2026-99999 · Updated 2026-10-19T22:17:28.667 - http://www.openwall.com/lists/oss-security/2026/10/15/5CVE record · CVE · Updated 2026-10-15T22:07:24.590Z
NVD · CVE-2026-99999 · Updated 2026-10-19T22:17:28.667 - https://access.redhat.com/security/cve/CVE-2026-99999 Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://bugzilla.redhat.com/show_bug.cgi?id=2553429 Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://www.cve.org/CVERecord?id=CVE-2026-99999 Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://nvd.nist.gov/vuln/detail/CVE-2026-99999 Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-99999.mbox Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://access.redhat.com/errata/RHSA-2026:85928 Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://access.redhat.com/errata/RHSA-2026:88206 Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://access.redhat.com/errata/RHSA-2026:85321 Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://access.redhat.com/errata/RHSA-2026:86089 Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://access.redhat.com/errata/RHSA-2026:86033 Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://access.redhat.com/errata/RHSA-2026:89083 Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://access.redhat.com/errata/RHSA-2026:87086 Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://access.redhat.com/errata/RHSA-2026:87821 Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://access.redhat.com/errata/RHSA-2026:87822 Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://access.redhat.com/errata/RHSA-2026:88204 Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://access.redhat.com/errata/RHSA-2026:85979 Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://access.redhat.com/errata/RHSA-2026:87264 Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://access.redhat.com/errata/RHSA-2026:87091 Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://access.redhat.com/errata/RHSA-2026:87098 Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://access.redhat.com/errata/RHSA-2026:89082 Red Hat · CVE-2026-99999 · Updated 2026-10-26T13:27:30+00:00
- https://access.redhat.com/security/cve/cve-2026-99999 VulnCheck KEV · CVE-2026-99999 · Updated 2026-10-19T00:00:00Z
- https://vulncheck.com/xdb/d78be1b0f067 VulnCheck KEV · d78be1b0f067 · Updated 2026-10-19T00:00:00Z
- https://github.com/PeronGH/CVE-2026-99999 VulnCheck KEV · d78be1b0f067 · Updated 2026-10-19T00:00:00Z
- https://vulncheck.com/xdb/319a7fb4465f VulnCheck KEV · 319a7fb4465f · Updated 2026-10-19T00:00:00Z
- https://github.com/gandli/CVE-2026-99999-pwnescape VulnCheck KEV · 319a7fb4465f · Updated 2026-10-19T00:00:00Z