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TI-2026-31365 Aliases CVE-2026-43186GHSA-8x8h-4g2v-qpf2

ipv6: ioam: fix heap buffer overflow in __ioam6_fill_trace_data()

Priority MEDIUM 50CWE-122Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 10 fixed, 1 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-122 and the CVSS impact.

Summary

In the Linux kernel, the following vulnerability has been resolved: ipv6: ioam: fix heap buffer overflow in __ioam6_fill_trace_data() On the receive path, __ioam6_fill_trace_data() uses trace->nodelen to decide how much data to write for each node. It trusts this field as-is from the incoming packet, with no consistency check against trace->type (the 24-bit field that tells which data items are present). A crafted packet can set nodelen=0 while setting type bits 0-21, causing the function to write ~100 bytes past the allocated region (into skb_shared_info), which corrupts adjacent heap memory and leads to a kernel panic. Add a shared helper ioam6_trace_compute_nodelen() in ioam6.c to derive the expected nodelen from the type field, and use it: - in ioam6_iptunnel.c (send path, existing validation) to replace the open-coded computation; - in exthdrs.c (receive path, ipv6_hop_ioam) to drop packets whose nodelen is inconsistent with the type field, before any data is written. Per RFC 9197, bits 12-21 are each short (4-octet) fields, so they are included in IOAM6_MASK_SHORT_FIELDS (changed from 0xff100000 to 0xff1ffc00).

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00642 51st percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.15.202, 6.1.165, 6.6.128 +4Red Hat: 2 advisoriesRed Hat: 10 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.15 and later5.15.202, 6.1.165, 6.6.128, 6.12.75, 6.18.16, 6.19.6, 7.0Patch availableCNA
  • Linux VendorLinux Affected 5.15 and later Fixed in 5.15.202, 6.1.165, 6.6.128, 6.12.75, 6.18.16, 6.19.6, 7.0 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*5.15 to before 5.15.202; 5.16 to before 6.1.165; 6.2 to before 6.6.128; 6.7 to before 6.12.75; 6.13 to before 6.18.16; 6.19 to before 6.19.6VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.15 to before 5.15.202; 5.16 to before 6.1.165; 6.2 to before 6.6.128; 6.7 to before 6.12.75; 6.13 to before 6.18.16; 6.19 to before 6.19.6 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 5.15.202, 6.1.165, 6.6.128, 6.12.75, 6.18.16, 6.19.6, 7.0

Red Hat 2 advisories

  • RHSA-2026:77634 Released 2026-10-08 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) kernel-64k-debug-devel-6.12.0-55.109.1.el10_0, kernel-64k-debug-devel-matched-6.12.0-55.109.1.el10_0, kernel-64k-devel-6.12.0-55.109.1.el10_0 +12
    • Red Hat Enterprise Linux BaseOS EUS (v. 10.0) kernel-6.12.0-55.109.1.el10_0, kernel-64k-6.12.0-55.109.1.el10_0, kernel-64k-core-6.12.0-55.109.1.el10_0 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) kernel-tools-libs-devel-6.12.0-55.109.1.el10_0, libperf-6.12.0-55.109.1.el10_0
    • Red Hat Enterprise Linux Real Time EUS (v. 10.0) kernel-rt-6.12.0-55.109.1.el10_0, kernel-rt-64k-6.12.0-55.109.1.el10_0, kernel-rt-64k-core-6.12.0-55.109.1.el10_0 +21
    • Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0) kernel-rt-6.12.0-55.109.1.el10_0, kernel-rt-core-6.12.0-55.109.1.el10_0, kernel-rt-debug-6.12.0-55.109.1.el10_0 +11
  • RHSA-2026:51295 Released 2026-08-06 · Red Hat rating Moderate
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-211.44.1.el10_2, kernel-64k-debug-devel-matched-6.12.0-211.44.1.el10_2, kernel-64k-devel-6.12.0-211.44.1.el10_2 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-211.44.1.el10_2, kernel-64k-6.12.0-211.44.1.el10_2, kernel-64k-core-6.12.0-211.44.1.el10_2 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-211.44.1.el10_2, libperf-6.12.0-211.44.1.el10_2
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-211.44.1.el10_2, kernel-rt-64k-6.12.0-211.44.1.el10_2, kernel-rt-64k-core-6.12.0-211.44.1.el10_2 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-211.44.1.el10_2, kernel-rt-core-6.12.0-211.44.1.el10_2, kernel-rt-debug-6.12.0-211.44.1.el10_2 +9

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:51295
Red Hat Enterprise Linux AppStream EUS (v. 10.0)Fixed RHSA-2026:77634
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:51295
Red Hat Enterprise Linux BaseOS EUS (v. 10.0)Fixed RHSA-2026:77634
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:51295
Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0)Fixed RHSA-2026:77634
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2026:51295
Red Hat Enterprise Linux Real Time EUS (v. 10.0)Fixed RHSA-2026:77634
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2026:51295
Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0)Fixed RHSA-2026:77634
Not affected: 3 products
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-43186
  2. 2026-10-03 Alias added: GHSA-8x8h-4g2v-qpf2
  3. 2026-10-09 Fix available: RHSA-2026:77634 · Red Hat
  4. 2026-10-09 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
  5. 2026-10-16 CISA SSVC decision points changed
  6. 2026-10-19 Weakness changed · CISA ADP

References

Patch 7

  • 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-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
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

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