CVE-2026-19662
MEDIUM 5.9An attacker may be able to cause a `named` resolver to abort. The attack requires inducing the victim resolver to send multiple queries for a DNSSEC-signed zone hosted by an authoritative server under the control of the attacker. If the auth responds with a particular sequence of crafted answers, and those answers arrive in a particular order with particular timing, the `named` resolver will encounter a use-after-free bug, and abort. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.27, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.27-S1.
No known exploitation, public exploit, or elevated probability at this time. Track for changes.
Exploitation likelihood
0.5%chance of exploitation in 30 days · 40th percentile
Impact if exploited
5.9CVSS 3.1 · MEDIUM
- 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: Needs a race window or specific setup
✓ 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-416: Use After Free
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
References and research data (JSON)
Vendor product assessments
Showing 32 of 232 vendor product statements; 200 omitted. Read the full vendor advisory.
bind-32:9.16.23-40.el9_8.12.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_8.12?arch=aarch64&epoch=32
- 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 Vendor guidance
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
bind-debugsource-32:9.16.23-40.el9_8.12.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 9) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_8.12?arch=x86_64&epoch=32
- 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 Vendor guidance
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
bind-libs-debuginfo-32:9.16.23-40.el9_8.12.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 9) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_8.12?arch=x86_64&epoch=32
- 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 Vendor guidance
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
bind9.18-chroot-32:9.18.29-14.el9_8.11.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 9) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_8.11?arch=ppc64le&epoch=32
- 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 Vendor guidance
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
bind9.18-dnssec-utils-debuginfo-32:9.18.29-14.el9_8.11.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 9) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_8.11?arch=ppc64le&epoch=32
- 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 Vendor guidance
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
bind9.18-utils-debuginfo-32:9.18.29-14.el9_8.11.s390x as a component of Red Hat Enterprise Linux AppStream (v. 9) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_8.11?arch=s390x&epoch=32
- 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 Vendor guidance
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
bind-devel-32:9.16.23-40.el9_8.12.s390x as a component of Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_8.12?arch=s390x&epoch=32
- 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 Vendor guidance
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
bind-utils-debuginfo-32:9.16.23-40.el9_8.12.ppc64le as a component of Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_8.12?arch=ppc64le&epoch=32
- 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 Vendor guidance
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
bind9.18-devel-32:9.18.29-14.el9_8.11.s390x as a component of Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_8.11?arch=s390x&epoch=32
- 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 Vendor guidance
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
bind9.18-utils-debuginfo-32:9.18.29-14.el9_8.11.s390x as a component of Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) · fixed
Vendor assessment for this product only.
pkg:rpm/redhat/[email protected]_8.11?arch=s390x&epoch=32
- 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 Vendor guidance
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
bind-utils-32:9.20.29-0.1.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
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
bind as a component of Red Hat Enterprise Linux 10 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
- 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
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
- none available: Affected
bind-devel as a component of Red Hat Enterprise Linux 7 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind-devel
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
- none available: Fix deferred
bind-license as a component of Red Hat Enterprise Linux 7 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind-license
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
- none available: Fix deferred
bind-sdb as a component of Red Hat Enterprise Linux 7 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind-sdb
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
- none available: Fix deferred
bind-devel as a component of Red Hat Enterprise Linux 8 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind-devel
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
- none available: Fix deferred
bind-license as a component of Red Hat Enterprise Linux 8 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind-license
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
- none available: Fix deferred
bind-pkcs11-utils as a component of Red Hat Enterprise Linux 8 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind-pkcs11-utils
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
- none available: Fix deferred
bind9.16-chroot as a component of Red Hat Enterprise Linux 8 · known affected
Vendor assessment for this product only.
pkg:rpm/redhat/bind9.16-chroot
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
- none available: Fix deferred
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
- workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
- none available: Fix deferred
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: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named`
- none available: Fix deferred
bind as a component of Red Hat Enterprise Linux 6 · known not affected
Vendor assessment for this product only.
Reason: vulnerable code not present
pkg:rpm/redhat/bind
Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00bind-chroot as a component of Red Hat Enterprise Linux 6 · known not affected
Vendor assessment for this product only.
Reason: vulnerable code not present
pkg:rpm/redhat/bind-chroot
Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00bind-devel as a component of Red Hat Enterprise Linux 6 · known not affected
Vendor assessment for this product only.
Reason: vulnerable code not present
pkg:rpm/redhat/bind-devel
Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00bind-sdb as a component of Red Hat Enterprise Linux 6 · known not affected
Vendor assessment for this product only.
Reason: vulnerable code not present
pkg:rpm/redhat/bind-sdb
Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00bind-utils as a component of Red Hat Enterprise Linux 6 · known not affected
Vendor assessment for this product only.
Reason: vulnerable code not present
pkg:rpm/redhat/bind-utils
Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00bind.src as a component of Red Hat Enterprise Linux 6 · known not affected
Vendor assessment for this product only.
Reason: vulnerable code not present
pkg:rpm/redhat/bind?arch=src
Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00dhcp-client as a component of Red Hat Enterprise Linux 9 · known not affected
Vendor assessment for this product only.
Reason: vulnerable code not present
pkg:rpm/redhat/dhcp-client
Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00dhcp-relay as a component of Red Hat Enterprise Linux 9 · known not affected
Vendor assessment for this product only.
Reason: vulnerable code not present
pkg:rpm/redhat/dhcp-relay
Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00dhcp-server as a component of Red Hat Enterprise Linux 9 · known not affected
Vendor assessment for this product only.
Reason: vulnerable code not present
pkg:rpm/redhat/dhcp-server
Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00dhcp.src as a component of Red Hat Enterprise Linux 9 · known not affected
Vendor assessment for this product only.
Reason: vulnerable code not present
pkg:rpm/redhat/dhcp?arch=src
Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00
All CVSS metrics
- MEDIUM 5.9 v3.1 · CNA Primary
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - MEDIUM 5.9 v3.1 · NVD Secondary
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
References
Patches & mitigations
- https://downloads.isc.org/isc/bind9/9.20.29 CVE record · isc · Updated 2026-09-16T13:50:10.432Z
NVD · CVE-2026-19662 · Updated 2026-09-17T19:16:41.783
Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00
Advisories
- https://kb.isc.org/docs/cve-2026-19662 CVE record · isc · Updated 2026-09-16T13:50:10.432Z
NVD · CVE-2026-19662 · Updated 2026-09-17T19:16:41.783
Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00 - https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-19662.json Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-80743 EUVD · EUVD-2026-80743
Technical & other
- https://access.redhat.com/security/cve/CVE-2026-19662 Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00
- https://bugzilla.redhat.com/show_bug.cgi?id=2535445 Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00
- https://www.cve.org/CVERecord?id=CVE-2026-19662 Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00
- https://nvd.nist.gov/vuln/detail/CVE-2026-19662 Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00
- https://access.redhat.com/errata/RHSA-2026:89745 Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00
- https://access.redhat.com/errata/RHSA-2026:89746 Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00
- https://access.redhat.com/errata/RHSA-2026:68279 Red Hat · CVE-2026-19662 · Updated 2026-10-26T07:13:59+00:00