RHSA-2026:99168HighCVSS 7.5

Red Hat Security Advisory: c-ares security update

Published
November 11, 2026
Last Modified
November 11, 2026

🔗 CVE IDs covered (2)

CVE-2026-69184 →CVE-2026-69186 →

📋 Description

CVE-2026-69184 — c-ares: c-ares: CPU exhaustion denial of service via unbounded DNS name compression pointer chains CVE-2026-69186 — c-ares: c-ares: Denial of Service via unvalidated DNS header record counts

🎯 Affected products27

  • Red Hat Enterprise Linux AppStream EUS (v.10.2)
  • Red Hat Enterprise Linux BaseOS EUS (v.10.2)
  • c-ares-0:1.34.6-2.el10_2.2.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v.10.2)
  • c-ares-0:1.34.6-2.el10_2.2.ppc64le as a component of Red Hat Enterprise Linux BaseOS EUS (v.10.2)
  • c-ares-0:1.34.6-2.el10_2.2.s390x as a component of Red Hat Enterprise Linux BaseOS EUS (v.10.2)
  • c-ares-0:1.34.6-2.el10_2.2.src as a component of Red Hat Enterprise Linux BaseOS EUS (v.10.2)
  • c-ares-0:1.34.6-2.el10_2.2.x86_64 as a component of Red Hat Enterprise Linux BaseOS EUS (v.10.2)
  • c-ares-debuginfo-0:1.34.6-2.el10_2.2.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v.10.2)
  • c-ares-debuginfo-0:1.34.6-2.el10_2.2.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v.10.2)
  • c-ares-debuginfo-0:1.34.6-2.el10_2.2.ppc64le as a component of Red Hat Enterprise Linux AppStream EUS (v.10.2)
  • c-ares-debuginfo-0:1.34.6-2.el10_2.2.ppc64le as a component of Red Hat Enterprise Linux BaseOS EUS (v.10.2)
  • c-ares-debuginfo-0:1.34.6-2.el10_2.2.s390x as a component of Red Hat Enterprise Linux AppStream EUS (v.10.2)
  • c-ares-debuginfo-0:1.34.6-2.el10_2.2.s390x as a component of Red Hat Enterprise Linux BaseOS EUS (v.10.2)
  • c-ares-debuginfo-0:1.34.6-2.el10_2.2.x86_64 as a component of Red Hat Enterprise Linux AppStream EUS (v.10.2)
  • c-ares-debuginfo-0:1.34.6-2.el10_2.2.x86_64 as a component of Red Hat Enterprise Linux BaseOS EUS (v.10.2)
  • c-ares-debugsource-0:1.34.6-2.el10_2.2.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v.10.2)
  • c-ares-debugsource-0:1.34.6-2.el10_2.2.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v.10.2)
  • c-ares-debugsource-0:1.34.6-2.el10_2.2.ppc64le as a component of Red Hat Enterprise Linux AppStream EUS (v.10.2)
  • c-ares-debugsource-0:1.34.6-2.el10_2.2.ppc64le as a component of Red Hat Enterprise Linux BaseOS EUS (v.10.2)
  • c-ares-debugsource-0:1.34.6-2.el10_2.2.s390x as a component of Red Hat Enterprise Linux AppStream EUS (v.10.2)
  • c-ares-debugsource-0:1.34.6-2.el10_2.2.s390x as a component of Red Hat Enterprise Linux BaseOS EUS (v.10.2)
  • c-ares-debugsource-0:1.34.6-2.el10_2.2.x86_64 as a component of Red Hat Enterprise Linux AppStream EUS (v.10.2)
  • c-ares-debugsource-0:1.34.6-2.el10_2.2.x86_64 as a component of Red Hat Enterprise Linux BaseOS EUS (v.10.2)
  • c-ares-devel-0:1.34.6-2.el10_2.2.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v.10.2)
  • c-ares-devel-0:1.34.6-2.el10_2.2.ppc64le as a component of Red Hat Enterprise Linux AppStream EUS (v.10.2)
  • c-ares-devel-0:1.34.6-2.el10_2.2.s390x as a component of Red Hat Enterprise Linux AppStream EUS (v.10.2)
  • c-ares-devel-0:1.34.6-2.el10_2.2.x86_64 as a component of Red Hat Enterprise Linux AppStream EUS (v.10.2)

✅ Remediation

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 Workaround: Configure applications that use c-ares to query only trusted DNS resolvers over a trusted network path. Restrict DNS responses from untrusted sources so a malicious or on-path resolver cannot deliver crafted replies. Workaround: Configure applications that use c-ares to query only trusted DNS resolvers over a trusted network path (CME-202 host firewall; CME-203 network segmentation). Restrict DNS responses from untrusted sources so a malicious or on-path resolver cannot deliver crafted replies. There is no complete library-level workaround; apply a fixed c-ares update when available.

🔗 References (5)