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TI-2026-79656 Aliases CVE-2026-98899GHSA-ffrw-gp84-hx8m

Improper RCU locking in Linux kernel netfilter ipset

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
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

The Linux kernel netfilter ipset code is affected from 5.4.24 before 5.5, from 5.5.8 before 5.6, and from 5.6 onward. The code takes an RCU lock where none is needed when it bumps the uref counter, and mtype_gc uses a spinlock where an RCU lock is required. A local user with low privileges can exploit this flaw, with high impact to confidentiality, integrity and availability.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

In the Linux kernel, the following vulnerability has been resolved: netfilter: ipset: mark the rcu locked areas properly When we bump the uref counter, there's no need to keep the rcu lock because the referred hash table can't disappear. Also, from the same reason in mtype_gc we need the rcu lock and not a spinlock.

Why it matters now

EPSS 0.00169 6th percentileScored 2026-11-07
Fix Fixed Linux (Linux): 5.5, 5.6, 5.10.271 +6

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.4.24 to before 5.5; 5.5.8 to before 5.65.5, 5.6Patch availableCNA
LinuxLinux5.6 and later5.10.271, 5.15.222, 6.1.189, 6.6.158, 6.12.111, 6.18.53, 7.2Patch availableCNA
  • Linux VendorLinux Affected 5.4.24 to before 5.5; 5.5.8 to before 5.6 Fixed in 5.5, 5.6 Patch available CNA
  • Linux VendorLinux Affected 5.6 and later Fixed in 5.10.271, 5.15.222, 6.1.189, 6.6.158, 6.12.111, 6.18.53, 7.2 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

Update the Linux kernel to a fixed version: 5.5, 5.6, 5.10.271, 5.15.222, 6.1.189, 6.6.158, 6.12.111, 6.18.53 or 7.2.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA Linux (Linux) Fixed in 5.5, 5.6
  • Fix · CNA Linux (Linux) Fixed in 5.10.271, 5.15.222, 6.1.189, 6.6.158, 6.12.111, 6.18.53, 7.2

Timeline

  1. 2026-10-23 Threatist record created from CVE-2026-98899
  2. 2026-10-23 Alias added: GHSA-ffrw-gp84-hx8m
  3. 2026-10-24 CVSS score added · CNA
  4. 2026-10-24 Priority changed: LOW → MEDIUM
  5. 2026-10-24 Priority changed: MEDIUM → LOW
  6. 2026-10-26 Fix available: Linux/Linux@0, Linux/[email protected], Linux/[email protected] · CNA

References

Other 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-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 21727 →

Sources

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