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TI-2025-26439 Aliases CVE-2025-39764GHSA-rh5v-2xrc-gj9x

netfilter: ctnetlink: remove refcounting in expectation dumpers

Priority LOW 24Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 5 without a fix

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

Summary

In the Linux kernel, the following vulnerability has been resolved: netfilter: ctnetlink: remove refcounting in expectation dumpers Same pattern as previous patch: do not keep the expectation object alive via refcount, only store a cookie value and then use that as the skip hint for dump resumption. AFAICS this has the same issue as the one resolved in the conntrack dumper, when we do if (!refcount_inc_not_zero(&exp->use)) to increment the refcount, there is a chance that exp == last, which causes a double-increment of the refcount and subsequent memory leak.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00173 6th percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.10.253, 5.15.203, 6.1.167 +4Red Hat: 5 without a fix

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

VendorProductAffected versionsFixed inStatusSource
LinuxLinux2.6.23 and later5.10.253, 5.15.203, 6.1.167, 6.6.130, 6.12.78, 6.16.2, 6.17Patch availableCNA
  • Linux VendorLinux Affected 2.6.23 and later Fixed in 5.10.253, 5.15.203, 6.1.167, 6.6.130, 6.12.78, 6.16.2, 6.17 Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*2.6.23 to before 6.16.2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*6.17 rc1VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 2.6.23 to before 6.16.2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:* Versions 6.17 rc1 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 5.10.253, 5.15.203, 6.1.167, 6.6.130, 6.12.78, 6.16.2, 6.17

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

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-39764
  2. 2026-10-03 Alias added: GHSA-rh5v-2xrc-gj9x
  3. 2026-11-05 CISA SSVC decision points changed

References

Patch 2

Other 5

  • 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