Read the docs
TI-2026-68132 Aliases CVE-2026-98241GHSA-5mfq-x364-3h2r

Request socket misuse in Linux kernel IPv6 XFRM error handling

Priority LOW 33Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 7 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.

Summary

The Linux kernel IPv6 XFRM local PMTU and error handlers assume the socket attached to a packet is a full socket. A TCP SYN-ACK can carry a request socket instead, so the handlers can read past its allocation. A local user with low privileges can trigger this when rerouting selects an XFRM tunnel route with a smaller MTU.

Written with Claude Haiku 5.5 from the sources below · 2026-10-30

Description from the CNA

In the Linux kernel, the following vulnerability has been resolved: ipv6: xfrm: use full sockets in local error paths xfrm6_local_rxpmtu() and xfrm6_local_error() dereference skb->sk as if it always pointed at a full IPv6 socket. That is not guaranteed. TCP SYN-ACK skbs can be owned by a TCP_NEW_SYN_RECV request_sock while the output path itself is driven by the full listener. If rerouting selects an IPv6 XFRM tunnel route with a lower MTU, the local PMTU/error handling path can reach these callbacks with that mini-socket still attached to the skb. The callbacks then miscast the request socket as a full inet/IPv6 socket and can read beyond the request_sock allocation when they access inet_sock or ipv6_pinfo state. Resolve the owner with skb_to_full_sk() in both callbacks and bail out when no full socket is attached. This matches the surrounding XFRM IPv6 PMTU/error logic, which already reasons about full sockets with skb_to_full_sk().

Why it matters now

EPSS 0.00129 2nd percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.10.271, 5.15.222, 6.1.189 +5Red Hat: 7 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux3.2 and later5.10.271, 5.15.222, 6.1.189, 6.6.158, 6.12.112, 6.18.54, 7.2.8, 7.3Patch availableCNA
  • Linux VendorLinux Affected 3.2 and later Fixed in 5.10.271, 5.15.222, 6.1.189, 6.6.158, 6.12.112, 6.18.54, 7.2.8, 7.3 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*——Linux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions — — ·Linux

Remediation

The Linux kernel is fixed in 5.10.271, 5.15.222, 6.1.189, 6.6.158, 6.12.112, 6.18.54, 7.2.8 and 7.3. Red Hat rates this Moderate and lists Red Hat Enterprise Linux 6 as no fix planned, and Red Hat Enterprise Linux 7, 8, 9, 10, OpenShift Container Platform 4 and OpenShift Container Platform 5 with no plan available.

Written with Claude Haiku 5.5 from the sources below · 2026-10-30

  • Fix · CNA Linux (Linux) Fixed in 5.10.271, 5.15.222, 6.1.189, 6.6.158, 6.12.112, 6.18.54, 7.2.8, 7.3

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 4AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 5AffectedNo fix yet: Fix deferred

Timeline

  1. 2026-10-06 Threatist record created from CVE-2026-98241
  2. 2026-10-06 Alias added: GHSA-5mfq-x364-3h2r
  3. 2026-10-07 CVSS score added · CNA
  4. 2026-10-10 Affected versions changed · Red Hat
  5. 2026-10-10 CVSS score added · Red Hat
  6. 2026-10-19 Fix available: Linux/[email protected] · CNA
  7. 2026-10-30 Affected versions changed · Red Hat
  8. 2026-11-03 Affected versions changed · Red Hat
  9. 2026-11-03 CVSS score changed · Red Hat

References

Other 8

  • 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
See all 21741 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences