ipv6: fix use-after-free in ip6_finish_output2()
Key facts
- Attack vector
- —
- Privileges required
- —
- User interaction
- —
- Attack complexity
- —
- Impact type
- —
- Confidentiality · integrity · availability
- —
- Fix status
- Partial Red Hat: 36 fixed, 2 without a fix
No CVSS vector from any source. Fix status from CNA and Red Hat.
Summary
In the Linux kernel, the following vulnerability has been resolved: ipv6: fix use-after-free in ip6_finish_output2() ip6_finish_output2() caches a pointer to the IPv6 destination address (daddr) before invoking lwtunnel_xmit(). The LWT-BPF transmit path or other encapsulation operations within lwtunnel_xmit() can reallocate the skb head, freeing the memory that daddr points to. When lwtunnel_xmit() returns LWTUNNEL_XMIT_CONTINUE, the function continues to use the stale daddr pointer to compute the nexthop and to look up or create the neighbour entry. This results in a use-after-free read, which can leak sensitive kernel data, pollute the neighbour table with arbitrary values, misdirect traffic, or crash the system. Fix this by re-fetching the IPv6 header and the destination address pointer after lwtunnel_xmit() returns LWTUNNEL_XMIT_CONTINUE, ensuring that the subsequent nexthop computation and neighbour lookup operate on valid memory.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.10.267, 5.5
- Fix · CNA Linux (Linux) Fixed in 5.10.267, 5.15.218, 6.1.185, 6.6.154, 6.12.106, 6.18.47, 7.1.11, 7.2.1, 7.3
Red Hat 13 advisories
- RHSA-2026:93047 Released 2026-10-30 · Red Hat rating Importantkernel-rt security, bug fix, and enhancement update
- Red Hat Enterprise Linux Real Time E4S (v.9.2) kernel-rt-5.14.0-284.200.1.rt14.485.el9_2, kernel-rt-core-5.14.0-284.200.1.rt14.485.el9_2, kernel-rt-debug-5.14.0-284.200.1.rt14.485.el9_2 +9
- Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2) kernel-rt-5.14.0-284.200.1.rt14.485.el9_2, kernel-rt-core-5.14.0-284.200.1.rt14.485.el9_2, kernel-rt-debug-5.14.0-284.200.1.rt14.485.el9_2 +11
- RHSA-2026:92993 Released 2026-10-30 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream E4S (v.9.2) kernel-64k-debug-devel-5.14.0-284.200.1.el9_2, kernel-64k-debug-devel-matched-5.14.0-284.200.1.el9_2, kernel-64k-devel-5.14.0-284.200.1.el9_2 +10
- Red Hat Enterprise Linux BaseOS E4S (v.9.2) bpftool-7.0.0-284.200.1.el9_2, kernel-5.14.0-284.200.1.el9_2, kernel-64k-5.14.0-284.200.1.el9_2 +29
- RHSA-2026:89197 Released 2026-10-27 · Red Hat rating CriticalOpenShift Container Platform 4.22.20 bug fix and security update
- Red Hat OpenShift Container Platform 4.22 rhcos-aarch64-4.22.9.8.202610241758-0, rhcos-ppc64le-4.22.9.8.202610241758-0, rhcos-s390x-4.22.9.8.202610241758-0 +1
Show 10 more Red Hat advisories
- RHSA-2026:89714 Released 2026-10-27 · Red Hat rating CriticalOpenShift Container Platform 4.16.74 bug fix and security update
- Red Hat OpenShift Container Platform 4.16 rhcos-aarch64-416.94.202610242150-0, rhcos-ppc64le-416.94.202610242150-0, rhcos-s390x-416.94.202610242150-0 +1
- RHSA-2026:89725 Released 2026-10-27 · Red Hat rating CriticalOpenShift Container Platform 4.18.59 bug fix and security update
- Red Hat OpenShift Container Platform 4.18 rhcos-aarch64-418.94.202610242013-0, rhcos-ppc64le-418.94.202610242013-0, rhcos-s390x-418.94.202610242013-0 +1
- RHSA-2026:89651 Released 2026-10-27 · Red Hat rating CriticalOpenShift Container Platform 4.19.53 bug fix and security update
- Red Hat OpenShift Container Platform 4.19 rhcos-aarch64-4.19.9.6.202610241701-0, rhcos-ppc64le-4.19.9.6.202610241701-0, rhcos-s390x-4.19.9.6.202610241701-0 +1
- RHSA-2026:89232 Released 2026-10-27 · Red Hat rating CriticalOpenShift Container Platform 4.21.40 bug fix and security update
- Red Hat OpenShift Container Platform 4.21 rhcos-aarch64-4.21.9.6.202610241345-0, rhcos-ppc64le-4.21.9.6.202610241345-0, rhcos-s390x-4.21.9.6.202610241345-0 +1
- RHSA-2026:89333 Released 2026-10-27 · Red Hat rating CriticalOpenShift Container Platform 4.20.44 bug fix and security update
- Red Hat OpenShift Container Platform 4.20 rhcos-aarch64-4.20.9.6.202610242033-0, rhcos-ppc64le-4.20.9.6.202610242033-0, rhcos-s390x-4.20.9.6.202610242033-0 +1
- RHSA-2026:83707 Released 2026-10-16 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream EUS (v. 10.0) kernel-64k-debug-devel-6.12.0-55.111.1.el10_0, kernel-64k-debug-devel-matched-6.12.0-55.111.1.el10_0, kernel-64k-devel-6.12.0-55.111.1.el10_0 +12
- Red Hat Enterprise Linux BaseOS EUS (v. 10.0) kernel-6.12.0-55.111.1.el10_0, kernel-64k-6.12.0-55.111.1.el10_0, kernel-64k-core-6.12.0-55.111.1.el10_0 +28
- Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) kernel-tools-libs-devel-6.12.0-55.111.1.el10_0, libperf-6.12.0-55.111.1.el10_0
- Red Hat Enterprise Linux Real Time EUS (v. 10.0) kernel-rt-6.12.0-55.111.1.el10_0, kernel-rt-64k-6.12.0-55.111.1.el10_0, kernel-rt-64k-core-6.12.0-55.111.1.el10_0 +21
- Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0) kernel-rt-6.12.0-55.111.1.el10_0, kernel-rt-core-6.12.0-55.111.1.el10_0, kernel-rt-debug-6.12.0-55.111.1.el10_0 +11
- RHSA-2026:76739 Released 2026-10-08 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-687.55.1.el9_8, kernel-64k-debug-devel-matched-5.14.0-687.55.1.el9_8, kernel-64k-devel-5.14.0-687.55.1.el9_8 +12
- Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-687.55.1.el9_8, kernel-64k-5.14.0-687.55.1.el9_8, kernel-64k-core-5.14.0-687.55.1.el9_8 +28
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-687.55.1.el9_8, libperf-5.14.0-687.55.1.el9_8
- Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-687.55.1.el9_8, kernel-rt-64k-5.14.0-687.55.1.el9_8, kernel-rt-64k-core-5.14.0-687.55.1.el9_8 +21
- Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-687.55.1.el9_8, kernel-rt-core-5.14.0-687.55.1.el9_8, kernel-rt-debug-5.14.0-687.55.1.el9_8 +9
- RHSA-2026:77219 Released 2026-10-08 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat CodeReady Linux Builder EUS (v.9.6) kernel-tools-libs-devel-5.14.0-570.147.1.el9_6, libperf-5.14.0-570.147.1.el9_6
- Red Hat Enterprise Linux AppStream EUS (v.9.6) kernel-64k-debug-devel-5.14.0-570.147.1.el9_6, kernel-64k-debug-devel-matched-5.14.0-570.147.1.el9_6, kernel-64k-devel-5.14.0-570.147.1.el9_6 +12
- Red Hat Enterprise Linux BaseOS EUS (v.9.6) kernel-5.14.0-570.147.1.el9_6, kernel-64k-5.14.0-570.147.1.el9_6, kernel-64k-core-5.14.0-570.147.1.el9_6 +28
- Red Hat Enterprise Linux Real Time EUS (v.9.6) kernel-rt-5.14.0-570.147.1.el9_6, kernel-rt-64k-5.14.0-570.147.1.el9_6, kernel-rt-64k-core-5.14.0-570.147.1.el9_6 +21
- Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6) kernel-rt-5.14.0-570.147.1.el9_6, kernel-rt-core-5.14.0-570.147.1.el9_6, kernel-rt-debug-5.14.0-570.147.1.el9_6 +11
- RHSA-2026:76738 Released 2026-10-08 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- 10Base-SMTV kernel-modules-internal-6.12.0-211.63.1.el10_2
- Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-211.63.1.el10_2, kernel-64k-debug-devel-matched-6.12.0-211.63.1.el10_2, kernel-64k-devel-6.12.0-211.63.1.el10_2 +12
- Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-211.63.1.el10_2, kernel-64k-6.12.0-211.63.1.el10_2, kernel-64k-core-6.12.0-211.63.1.el10_2 +29
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-211.63.1.el10_2, libperf-6.12.0-211.63.1.el10_2
- Red Hat Enterprise Linux Hidden (v. 10) kernel-modules-internal-6.12.0-211.63.1.el10_2
- Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-211.63.1.el10_2, kernel-rt-64k-6.12.0-211.63.1.el10_2, kernel-rt-64k-core-6.12.0-211.63.1.el10_2 +21
- Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-211.63.1.el10_2, kernel-rt-core-6.12.0-211.63.1.el10_2, kernel-rt-debug-6.12.0-211.63.1.el10_2 +9
- RHSA-2026:77218 Released 2026-10-07 · Red Hat rating Importantkernel security update
- Red Hat Enterprise Linux AppStream E4S (v.9.4) kernel-64k-debug-devel-5.14.0-427.154.1.el9_4, kernel-64k-debug-devel-matched-5.14.0-427.154.1.el9_4, kernel-64k-devel-5.14.0-427.154.1.el9_4 +11
- Red Hat Enterprise Linux BaseOS E4S (v.9.4) bpftool-7.3.0-427.154.1.el9_4, kernel-5.14.0-427.154.1.el9_4, kernel-64k-5.14.0-427.154.1.el9_4 +29
- Red Hat Enterprise Linux Real Time E4S (v.9.4) kernel-rt-5.14.0-427.154.1.el9_4, kernel-rt-core-5.14.0-427.154.1.el9_4, kernel-rt-debug-5.14.0-427.154.1.el9_4 +9
- Red Hat Enterprise Linux Real Time for NFV E4S (v.9.4) kernel-rt-5.14.0-427.154.1.el9_4, kernel-rt-core-5.14.0-427.154.1.el9_4, kernel-rt-debug-5.14.0-427.154.1.el9_4 +11
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 9 | Affected | No fix yet |
| Red Hat OpenShift Container Platform 5 | Affected | No fix yet |
| 10Base-SMTV | Fixed | RHSA-2026:76738 |
| Red Hat CodeReady Linux Builder EUS (v.9.6) | Fixed | RHSA-2026:77219 |
| Red Hat Enterprise Linux AppStream (v. 10) | Fixed | RHSA-2026:76738 |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2026:76739 |
| Red Hat Enterprise Linux AppStream E4S (v.9.2) | Fixed | RHSA-2026:92993 |
| Red Hat Enterprise Linux AppStream E4S (v.9.4) | Fixed | RHSA-2026:77218 |
| Red Hat Enterprise Linux AppStream EUS (v. 10.0) | Fixed | RHSA-2026:83707 |
| Red Hat Enterprise Linux AppStream EUS (v.9.6) | Fixed | RHSA-2026:77219 |
| Red Hat Enterprise Linux BaseOS (v. 10) | Fixed | RHSA-2026:76738 |
| Red Hat Enterprise Linux BaseOS (v. 9) | Fixed | RHSA-2026:76739 |
| Red Hat Enterprise Linux BaseOS E4S (v.9.2) | Fixed | RHSA-2026:92993 |
| Red Hat Enterprise Linux BaseOS E4S (v.9.4) | Fixed | RHSA-2026:77218 |
| Red Hat Enterprise Linux BaseOS EUS (v. 10.0) | Fixed | RHSA-2026:83707 |
| Red Hat Enterprise Linux BaseOS EUS (v.9.6) | Fixed | RHSA-2026:77219 |
| Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) | Fixed | RHSA-2026:76738 |
| Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) | Fixed | RHSA-2026:76739 |
| Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) | Fixed | RHSA-2026:83707 |
| Red Hat Enterprise Linux Hidden (v. 10) | Fixed | RHSA-2026:76738 |
| Red Hat Enterprise Linux Real Time (v. 10) | Fixed | RHSA-2026:76738 |
| Red Hat Enterprise Linux Real Time (v. 9) | Fixed | RHSA-2026:76739 |
| Red Hat Enterprise Linux Real Time E4S (v.9.2) | Fixed | RHSA-2026:93047 |
| Red Hat Enterprise Linux Real Time E4S (v.9.4) | Fixed | RHSA-2026:77218 |
| Red Hat Enterprise Linux Real Time EUS (v. 10.0) | Fixed | RHSA-2026:83707 |
| Red Hat Enterprise Linux Real Time EUS (v.9.6) | Fixed | RHSA-2026:77219 |
| Red Hat Enterprise Linux Real Time for NFV (v. 10) | Fixed | RHSA-2026:76738 |
| Red Hat Enterprise Linux Real Time for NFV (v. 9) | Fixed | RHSA-2026:76739 |
| Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2) | Fixed | RHSA-2026:93047 |
| Red Hat Enterprise Linux Real Time for NFV E4S (v.9.4) | Fixed | RHSA-2026:77218 |
| Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0) | Fixed | RHSA-2026:83707 |
| Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6) | Fixed | RHSA-2026:77219 |
| Red Hat OpenShift Container Platform 4.16 | Fixed | RHSA-2026:89714 |
| Red Hat OpenShift Container Platform 4.18 | Fixed | RHSA-2026:89725 |
| Red Hat OpenShift Container Platform 4.19 | Fixed | RHSA-2026:89651 |
| Red Hat OpenShift Container Platform 4.20 | Fixed | RHSA-2026:89333 |
| Red Hat OpenShift Container Platform 4.21 | Fixed | RHSA-2026:89232 |
| Red Hat OpenShift Container Platform 4.22 | Fixed | RHSA-2026:89197 |
Not affected: 4 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat OpenShift Container Platform 4
Timeline
- 2026-10-02 Threatist record created from CVE-2026-80792
- 2026-10-03 Alias added: GHSA-4jhv-hqg8-9j35
- 2026-10-07 Fix available: RHSA-2026:77218 · Red Hat
- 2026-10-07 Fix available: Red Hat Enterprise Linux AppStream E4S (v.9.4), Red Hat Enterprise Linux BaseOS E4S (v.9.4), Red Hat Enterprise Linux Real Time E4S (v.9.4) +1 · Red Hat
- 2026-10-08 Fix available: Red Hat CodeReady Linux Builder EUS (v.9.6), Red Hat Enterprise Linux AppStream EUS (v.9.6), Red Hat Enterprise Linux BaseOS EUS (v.9.6) +2 · Red Hat
- 2026-10-09 Fix available: RHSA-2026:77219 · Red Hat
- 2026-10-09 Fix available: RHSA-2026:76739 · Red Hat
- 2026-10-09 Fix available: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9), Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) +2 · Red Hat
- 2026-10-18 Fix available: RHSA-2026:83707 · Red Hat
- 2026-10-18 Fix available: 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) +2 · Red Hat
- 2026-10-19 Fix available: Linux/[email protected] · CNA
- 2026-10-26 Fix available: RHSA-2026:76738 · Red Hat
- 2026-10-26 Fix available: 10Base-SMTV, Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10) +4 · Red Hat
- 2026-10-27 Fix available: Red Hat OpenShift Container Platform 4.16, Red Hat OpenShift Container Platform 4.18 · Red Hat
- 2026-10-28 Fix available: Red Hat OpenShift Container Platform 4.22 · Red Hat
- 2026-10-28 Fix available: Red Hat OpenShift Container Platform 4.19, Red Hat OpenShift Container Platform 4.20 · Red Hat
- 2026-10-29 Fix available: Red Hat OpenShift Container Platform 4.21 · Red Hat
- 2026-10-29 Fix available: RHSA-2026:89232 · Red Hat
- 2026-10-29 Fix available: RHSA-2026:89651 · Red Hat
- 2026-10-29 Fix available: RHSA-2026:89197 · Red Hat
- 2026-10-29 Fix available: RHSA-2026:89714 · Red Hat
- 2026-10-29 Fix available: RHSA-2026:89725 · Red Hat
- 2026-10-29 Fix available: RHSA-2026:89333 · Red Hat
- 2026-10-30 Affected versions changed · Red Hat
- 2026-10-30 Fix available: RHSA-2026:93047 · Red Hat
- 2026-10-30 Fix available: Red Hat Enterprise Linux AppStream E4S (v.9.2), Red Hat Enterprise Linux BaseOS E4S (v.9.2), Red Hat Enterprise Linux Real Time E4S (v.9.2) +1 · Red Hat
- 2026-10-31 Fix available: RHSA-2026:92993 · Red Hat
- 2026-11-06 CISA SSVC decision points changed
References
Other 9
- https://git.kernel.org/stable/c/75e0a544ebe9af663ef53ca21e9e9185c51fb54a
- https://git.kernel.org/stable/c/c95f01b78266828a57060d754fcbfc92123a98ed
- https://git.kernel.org/stable/c/d960881b9312e781a3429aabceb223ce6b7c882f
- https://git.kernel.org/stable/c/087ee0d914aaae929f1660c9ca878e367655ba1a
- https://git.kernel.org/stable/c/3c770ac4e6f07af7c7b40c474a3efc61ffed7862
- https://git.kernel.org/stable/c/3dc98e5fe82d069dd29b124ffbdb679331dfea43
- https://git.kernel.org/stable/c/99219c82804f266189388e8bf1cf5135d10d5515
- https://git.kernel.org/stable/c/73a187384a8c8b983c7fea046d716b6752a1e7a3
- https://git.kernel.org/stable/c/d0d48d999b0eee6bb176ef4e39d9be868fa80f7e
More Linux vulnerabilities
- TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2021-02452 Incorrect authorization in Ubuntu linux kernel KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
Sources
- CVE-2026-80792 · CVE Program
- CVE-2026-80792 · NVD
- FIRST EPSS
- GHSA-4jhv-hqg8-9j35 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-80792 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences