{"id":"CVE-2026-80792","title":"kernel: ipv6: fix use-after-free in ip6_finish_output2() (CVE-2026-80792)","summary":"A flaw was found in the Linux kernel's IPv6 networking stack. A use-after-free vulnerability exists in the `ip6_finish_output2()` function, where a cached pointer to the IPv6 destination address can become stale after memory reallocation. …","severity":"high","cvss":7,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","cvssSource":"vendor","cwe":"CWE-825","vendor":"Red Hat","product":"Red Hat Enterprise Linux BaseOS E4S (v.9.4)","affected":["enterprise_linux 9","openshift_container_platform 4","10base_smtv","enterprise_linux_appstream_eus_v_10_0","enterprise_linux_appstream_v_10","enterprise_linux_appstream_e4s_v_9_4","enterprise_linux_appstream_eus_v_9_6","enterprise_linux_appstream_v_9","enterprise_linux_baseos_eus_v_10_0","enterprise_linux_baseos_v_10","enterprise_linux_baseos_e4s_v_9_4","enterprise_linux_baseos_eus_v_9_6","enterprise_linux_baseos_v_9","enterprise_linux_codeready_linux_builder_eus_v_10_0","enterprise_linux_codeready_linux_builder_v_10","codeready_linux_builder_eus_v_9_6","enterprise_linux_codeready_linux_builder_v_9","enterprise_linux_hidden_v_10","enterprise_linux_real_time_for_nfv_eus_v_10_0","enterprise_linux_real_time_for_nfv_v_10","enterprise_linux_real_time_for_nfv_e4s_v_9_4","enterprise_linux_real_time_for_nfv_eus_v_9_6","enterprise_linux_real_time_for_nfv_v_9","enterprise_linux_real_time_eus_v_10_0","enterprise_linux_real_time_v_10","enterprise_linux_real_time_e4s_v_9_4","enterprise_linux_real_time_eus_v_9_6","enterprise_linux_real_time_v_9"],"patched":["10base_smtv","enterprise_linux_appstream_eus_v_10_0","enterprise_linux_appstream_v_10","enterprise_linux_appstream_e4s_v_9_4","enterprise_linux_appstream_eus_v_9_6","enterprise_linux_appstream_v_9","enterprise_linux_baseos_eus_v_10_0","enterprise_linux_baseos_v_10","enterprise_linux_baseos_e4s_v_9_4","enterprise_linux_baseos_eus_v_9_6","enterprise_linux_baseos_v_9","enterprise_linux_codeready_linux_builder_eus_v_10_0","enterprise_linux_codeready_linux_builder_v_10","codeready_linux_builder_eus_v_9_6","enterprise_linux_codeready_linux_builder_v_9","enterprise_linux_hidden_v_10","enterprise_linux_real_time_for_nfv_eus_v_10_0","enterprise_linux_real_time_for_nfv_v_10","enterprise_linux_real_time_for_nfv_e4s_v_9_4","enterprise_linux_real_time_for_nfv_eus_v_9_6","enterprise_linux_real_time_for_nfv_v_9","enterprise_linux_real_time_eus_v_10_0","enterprise_linux_real_time_v_10","enterprise_linux_real_time_e4s_v_9_4","enterprise_linux_real_time_eus_v_9_6","enterprise_linux_real_time_v_9"],"published":"2026-09-04","updated":"2026-10-26","sourceUpdated":"2026-10-26T09:35:54+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80792.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80792.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-80792"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2528542"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-80792"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-80792"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-80792.mbox"},{"url":"https://access.redhat.com/errata/RHSA-2026:76738"},{"url":"https://access.redhat.com/errata/RHSA-2026:83707"},{"url":"https://access.redhat.com/errata/RHSA-2026:77218"},{"url":"https://access.redhat.com/errata/RHSA-2026:77219"},{"url":"https://access.redhat.com/errata/RHSA-2026:76739"},{"url":"https://git.kernel.org/stable/c/75e0a544ebe9af663ef53ca21e9e9185c51fb54a"},{"url":"https://git.kernel.org/stable/c/c95f01b78266828a57060d754fcbfc92123a98ed"},{"url":"https://git.kernel.org/stable/c/d960881b9312e781a3429aabceb223ce6b7c882f"},{"url":"https://git.kernel.org/stable/c/087ee0d914aaae929f1660c9ca878e367655ba1a"},{"url":"https://git.kernel.org/stable/c/3c770ac4e6f07af7c7b40c474a3efc61ffed7862"},{"url":"https://git.kernel.org/stable/c/3dc98e5fe82d069dd29b124ffbdb679331dfea43"},{"url":"https://git.kernel.org/stable/c/99219c82804f266189388e8bf1cf5135d10d5515"},{"url":"https://git.kernel.org/stable/c/73a187384a8c8b983c7fea046d716b6752a1e7a3"},{"url":"https://git.kernel.org/stable/c/d0d48d999b0eee6bb176ef4e39d9be868fa80f7e"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.00195,"epssPercentile":0.09132,"ingestedAt":"2026-10-19T09:16:01.530Z","slug":"CVE-2026-80792","body":"## Overview\n\nA flaw was found in the Linux kernel's IPv6 networking stack. A use-after-free vulnerability exists in the `ip6_finish_output2()` function, where a cached pointer to the IPv6 destination address can become stale after memory reallocation. An attacker could potentially exploit this to leak sensitive kernel data, misdirect network traffic, or cause a system crash (Denial of Service).\n\n## Vendor advisories\n\n- **RHSA-2026:76738** · Red Hat · fixed in: 10Base-SMTV, Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10), Red Hat Enterprise Linux CodeReady Linux Builder (v. 10), Red Hat Enterprise Linux Hidden (v. 10), Red Hat Enterprise Linux Real Time for NFV (v. 10), … · released 2026-10-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:76738)\n- **RHSA-2026:83707** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v. 10.0), Red Hat Enterprise Linux BaseOS EUS (v. 10.0), Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0), Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0), Red Hat Enterprise Linux Real Time EUS (v. 10.0) · released 2026-10-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:83707)\n- **RHSA-2026:77218** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.4), Red Hat Enterprise Linux BaseOS E4S (v.9.4), Red Hat Enterprise Linux Real Time for NFV E4S (v.9.4), Red Hat Enterprise Linux Real Time E4S (v.9.4) · released 2026-10-07 · [advisory](https://access.redhat.com/errata/RHSA-2026:77218)\n- **RHSA-2026:77219** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v.9.6), Red Hat Enterprise Linux BaseOS EUS (v.9.6), Red Hat CodeReady Linux Builder EUS (v.9.6), Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6), Red Hat Enterprise Linux Real Time EUS (v.9.6) · released 2026-10-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:77219)\n- **RHSA-2026:76739** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9), Red Hat Enterprise Linux CodeReady Linux Builder (v. 9), Red Hat Enterprise Linux Real Time for NFV (v. 9), Red Hat Enterprise Linux Real Time (v. 9) · released 2026-10-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:76739)\n- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-10-26 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80792.json)\n\n**kernel: ipv6: fix use-after-free in ip6_finish_output2()** — rated Important by Red Hat. Released 2026-09-04, updated 2026-10-26.\n\nAffected:\n\n- Red Hat Enterprise Linux 9\n- Red Hat OpenShift Container Platform 4\n\nFixed:\n\n- 10Base-SMTV\n- Red Hat Enterprise Linux AppStream EUS (v. 10.0)\n- Red Hat Enterprise Linux AppStream (v. 10)\n- Red Hat Enterprise Linux AppStream E4S (v.9.4)\n- Red Hat Enterprise Linux AppStream EUS (v.9.6)\n- Red Hat Enterprise Linux AppStream (v. 9)\n- Red Hat Enterprise Linux BaseOS EUS (v. 10.0)\n- Red Hat Enterprise Linux BaseOS (v. 10)\n- Red Hat Enterprise Linux BaseOS E4S (v.9.4)\n- Red Hat Enterprise Linux BaseOS EUS (v.9.6)\n- Red Hat Enterprise Linux BaseOS (v. 9)\n- Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0)\n- Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)\n- Red Hat CodeReady Linux Builder EUS (v.9.6)\n- Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)\n- Red Hat Enterprise Linux Hidden (v. 10)\n- Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0)\n- Red Hat Enterprise Linux Real Time for NFV (v. 10)\n- Red Hat Enterprise Linux Real Time for NFV E4S (v.9.4)\n- Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6)\n- Red Hat Enterprise Linux Real Time for NFV (v. 9)\n- Red Hat Enterprise Linux Real Time EUS (v. 10.0)\n- Red Hat Enterprise Linux Real Time (v. 10)\n- Red Hat Enterprise Linux Real Time E4S (v.9.4)\n- Red Hat Enterprise Linux Real Time EUS (v.9.6)\n- Red Hat Enterprise Linux Real Time (v. 9)\n\nNo fix planned:\n\n- Red Hat Enterprise Linux 9\n- Red Hat OpenShift Container Platform 4\n\nNot affected:\n\n- Red Hat Enterprise Linux 6\n- Red Hat Enterprise Linux 7\n- Red Hat Enterprise Linux 8\n- Red Hat OpenShift Container Platform 4\n\n## Remediation\n\nFor details on how to apply this update, which includes the changes described in this advisory, refer to:\n\nhttps://access.redhat.com/articles/11258\n\nThe system must be rebooted for this update to take effect.\n\nRed 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.\n\nBecause of this proactive approach, a patch may be associa… https://access.redhat.com/errata/RHSA-2026:76738\nFor details on how to apply this update, which includes the changes described in this advisory, refer to:\n\nhttps://access.redhat.com/articles/11258\n\nThe system must be rebooted for this update to take effect.\n\nRed 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.\n\nBecause of this proactive approach, a patch may be associa… https://access.redhat.com/errata/RHSA-2026:83707\nFor details on how to apply this update, which includes the changes described in this advisory, refer to:\n\nhttps://access.redhat.com/articles/11258\n\nThe system must be rebooted for this update to take effect.\n\nRed 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.\n\nBecause of this proactive approach, a patch may be associa… https://access.redhat.com/errata/RHSA-2026:77218\n\nWorkarounds / mitigations:\n\n- 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.","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":38.5,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":229350,"id":"CVE-2026-80792","ts":1793019703765,"field":"cvss","old":null,"new":"7"},{"seq":229349,"id":"CVE-2026-80792","ts":1793019703765,"field":"severity","old":"none","new":"high"}]}