CVE-2026-19630
HIGH 7.5In a BIND resolver, inbound DNS protocol messages with a particular structure will result in additional processing, with no limit imposed by BIND. A DNS message with a maliciously large number of such structures will cause BIND to consume disproportionate amounts of CPU time and memory during processing. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.29, 9.21.0 through 9.21.26, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.29-S1.
Severe if exploited (CVSS 7.5), but no known exploitation and low modeled probability. Patch on a normal cadence.
Exploitation likelihood
0.4%chance of exploitation in 30 days · 39th percentile
Impact if exploited
7.5CVSS 3.1 · HIGH
- ConfidentialityNone
- IntegrityNone
- AvailabilityHigh
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ✓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
No public PoC is currently catalogued.
Search for new PoCs
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Tracked sources are checked daily for recent CVEs, including PoCs published after the original disclosure. A later release appears after a tracked source lists it and a refresh succeeds.
Data snapshot:
Weakness (CWE)
- CWE-407: Inefficient Algorithmic Complexity
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References and research data (JSON)
Vendor product assessments
Showing 32 of 109 vendor product statements; 77 omitted. Read the full vendor advisory.
bind-32:9.20.30-0.1.hum1@aarch64 as a component of Red Hat Hardened Images · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]?arch=aarch64&epoch=32&distro=hummingbird-20251124&repository_id=public-hummingbird-aarch64-rpms
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/ Vendor guidance
bind-32:9.20.30-0.1.hum1@s390x as a component of Red Hat Hardened Images · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]?arch=s390x&epoch=32&distro=hummingbird-20251124&repository_id=public-hummingbird-s390x-rpms
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/ Vendor guidance
bind-32:9.20.30-0.1.hum1@x86_64 as a component of Red Hat Hardened Images · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]?arch=x86_64&epoch=32&distro=hummingbird-20251124&repository_id=public-hummingbird-x86_64-rpms
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/ Vendor guidance
bind-chroot-32:9.20.30-0.1.hum1@aarch64 as a component of Red Hat Hardened Images · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]?arch=aarch64&epoch=32&distro=hummingbird-20251124&repository_id=public-hummingbird-aarch64-rpms
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/ Vendor guidance
bind-chroot-32:9.20.30-0.1.hum1@x86_64 as a component of Red Hat Hardened Images · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]?arch=x86_64&epoch=32&distro=hummingbird-20251124&repository_id=public-hummingbird-x86_64-rpms
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/ Vendor guidance
bind-devel-32:9.20.30-0.1.hum1@aarch64 as a component of Red Hat Hardened Images · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]?arch=aarch64&epoch=32&distro=hummingbird-20251124&repository_id=public-hummingbird-aarch64-rpms
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/ Vendor guidance
bind-devel-32:9.20.30-0.1.hum1@s390x as a component of Red Hat Hardened Images · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]?arch=s390x&epoch=32&distro=hummingbird-20251124&repository_id=public-hummingbird-s390x-rpms
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/ Vendor guidance
bind-dnssec-utils-32:9.20.30-0.1.hum1@aarch64 as a component of Red Hat Hardened Images · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]?arch=aarch64&epoch=32&distro=hummingbird-20251124&repository_id=public-hummingbird-aarch64-rpms
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/ Vendor guidance
bind-dnssec-utils-32:9.20.30-0.1.hum1@s390x as a component of Red Hat Hardened Images · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]?arch=s390x&epoch=32&distro=hummingbird-20251124&repository_id=public-hummingbird-s390x-rpms
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/ Vendor guidance
bind-doc-32:9.20.30-0.1.hum1@noarch@public-hummingbird-aarch64-rpms as a component of Red Hat Hardened Images · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]?arch=noarch&epoch=32&distro=hummingbird-20251124&repository_id=public-hummingbird-aarch64-rpms
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/ Vendor guidance
bind-doc-32:9.20.30-0.1.hum1@noarch@public-hummingbird-s390x-rpms as a component of Red Hat Hardened Images · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]?arch=noarch&epoch=32&distro=hummingbird-20251124&repository_id=public-hummingbird-s390x-rpms
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/ Vendor guidance
bind-doc-32:9.20.30-0.1.hum1@noarch@public-hummingbird-x86_64-rpms as a component of Red Hat Hardened Images · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]?arch=noarch&epoch=32&distro=hummingbird-20251124&repository_id=public-hummingbird-x86_64-rpms
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/ Vendor guidance
bind-libs-32:9.20.30-0.1.hum1@s390x as a component of Red Hat Hardened Images · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]?arch=s390x&epoch=32&distro=hummingbird-20251124&repository_id=public-hummingbird-s390x-rpms
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/ Vendor guidance
bind-libs-32:9.20.30-0.1.hum1@x86_64 as a component of Red Hat Hardened Images · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]?arch=x86_64&epoch=32&distro=hummingbird-20251124&repository_id=public-hummingbird-x86_64-rpms
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/ Vendor guidance
bind-utils-32:9.20.30-0.1.hum1@s390x as a component of Red Hat Hardened Images · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]?arch=s390x&epoch=32&distro=hummingbird-20251124&repository_id=public-hummingbird-s390x-rpms
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/ Vendor guidance
bind-utils-32:9.20.30-0.1.hum1@x86_64 as a component of Red Hat Hardened Images · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]?arch=x86_64&epoch=32&distro=hummingbird-20251124&repository_id=public-hummingbird-x86_64-rpms
- vendor fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/ Vendor guidance
bind as a component of Red Hat Enterprise Linux 10 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind
- none available: Affected
bind-license as a component of Red Hat Enterprise Linux 10 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind-license
- none available: Affected
bind-devel as a component of Red Hat Enterprise Linux 6 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind-devel
- none available: Affected
bind-chroot as a component of Red Hat Enterprise Linux 7 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind-chroot
- none available: Affected
bind-license as a component of Red Hat Enterprise Linux 7 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind-license
- none available: Affected
bind-sdb as a component of Red Hat Enterprise Linux 7 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind-sdb
- none available: Affected
bind-chroot as a component of Red Hat Enterprise Linux 8 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind-chroot
- none available: Affected
bind-license as a component of Red Hat Enterprise Linux 8 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind-license
- none available: Affected
bind-sdb as a component of Red Hat Enterprise Linux 8 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind-sdb
- none available: Affected
bind9.16-devel as a component of Red Hat Enterprise Linux 8 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind9.16-devel
- none available: Affected
bind9.16-utils as a component of Red Hat Enterprise Linux 8 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind9.16-utils
- none available: Affected
bind-devel as a component of Red Hat Enterprise Linux 9 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind-devel
- none available: Affected
bind-utils as a component of Red Hat Enterprise Linux 9 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind-utils
- none available: Affected
bind9.18-doc as a component of Red Hat Enterprise Linux 9 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind9.18-doc
- none available: Affected
dhcp-common as a component of Red Hat Enterprise Linux 9 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/dhcp-common
- 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
- none available: Affected
All CVSS metrics
- HIGH 7.5 v3.1 · CNA Primary
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - HIGH 7.5 v3.1 · NVD Secondary
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
Patches & mitigations
- https://downloads.isc.org/isc/bind9/9.20.30 CVE record · isc · Updated 2026-10-21T12:41:04.379Z
NVD · CVE-2026-19630 · Updated 2026-10-22T17:36:46.950 - https://downloads.isc.org/isc/bind9/9.21.27 CVE record · isc · Updated 2026-10-21T12:41:04.379Z
NVD · CVE-2026-19630 · Updated 2026-10-22T17:36:46.950
Advisories
- https://kb.isc.org/docs/cve-2026-19630 CVE record · isc · Updated 2026-10-21T12:41:04.379Z
NVD · CVE-2026-19630 · Updated 2026-10-22T17:36:46.950
Red Hat · CVE-2026-19630 · Updated 2026-10-22T20:32:06+00:00 - https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-19630.json Red Hat · CVE-2026-19630 · Updated 2026-10-22T20:32:06+00:00
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-107252 EUVD · EUVD-2026-107252
Technical & other
- https://access.redhat.com/security/cve/CVE-2026-19630 Red Hat · CVE-2026-19630 · Updated 2026-10-22T20:32:06+00:00
- https://bugzilla.redhat.com/show_bug.cgi?id=2556406 Red Hat · CVE-2026-19630 · Updated 2026-10-22T20:32:06+00:00
- https://www.cve.org/CVERecord?id=CVE-2026-19630 Red Hat · CVE-2026-19630 · Updated 2026-10-22T20:32:06+00:00
- https://nvd.nist.gov/vuln/detail/CVE-2026-19630 Red Hat · CVE-2026-19630 · Updated 2026-10-22T20:32:06+00:00
- https://access.redhat.com/errata/RHSA-2026:87309 Red Hat · CVE-2026-19630 · Updated 2026-10-22T20:32:06+00:00