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TI-2026-64497 Aliases CVE-2026-98099GHSA-5fxh-xwwm-73v4

ipv6: mcast: use rcu_assign_pointer() for __rcu list updates

Priority LOW 20CWE-362Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
High
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 7 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: ipv6: mcast: use rcu_assign_pointer() for __rcu list updates Several places in net/ipv6/mcast.c update RCU-protected lists (np->ipv6_mc_list, idev->mc_list, idev->mc_tomb) using direct pointer assignments instead of rcu_assign_pointer(): 1. In __ipv6_dev_mc_dec(), unlinking a group from idev->mc_list did: *map = ma->next; without rcu_assign_pointer() while concurrent readers traverse idev->mc_list locklessly under rcu_read_lock(). 2. In ipv6_sock_mc_drop() and __ipv6_sock_mc_close(), unlinking a group from np->ipv6_mc_list directly assigned *lnk = mc_lst->next and np->ipv6_mc_list = mc_lst->next without rcu_assign_pointer(), racing with lockless readers in inet6_mc_check(). 3. In __ipv6_sock_mc_join(), mc_lst->next was initialized to np->ipv6_mc_list via raw assignment before publishing mc_lst. 4. In mld_del_delrec() and __ipv6_dev_mc_inc(), __rcu source pointers passed into rcu_assign_pointer() lacked explicit dereference helpers. Fix these by consistently using rcu_assign_pointer() along with mc_dereference() / sock_dereference().

Why it matters now

EPSS 0.00091 0th percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.6.160, 6.12.114, 6.18.57 +2Red 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
LinuxLinux2.6.38 and later6.6.160, 6.12.114, 6.18.57, 7.2.7, 7.3Patch availableCNA
  • Linux VendorLinux Affected 2.6.38 and later Fixed in 6.6.160, 6.12.114, 6.18.57, 7.2.7, 7.3 Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*2.6.38 to before 6.6.160; 6.7 to before 6.12.114; 6.13 to before 6.18.57; 6.19 to before 7.2.7VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.3:rc1:*:*:*:*:*:*7.3 rc1VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 2.6.38 to before 6.6.160; 6.7 to before 6.12.114; 6.13 to before 6.18.57; 6.19 to before 7.2.7 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.3:rc1:*:*:*:*:*:* Versions 7.3 rc1 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.6.160, 6.12.114, 6.18.57, 7.2.7, 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. 2026-10-02 Threatist record created from CVE-2026-98099
  2. 2026-10-03 Alias added: GHSA-5fxh-xwwm-73v4
  3. 2026-10-16 Fix available: Linux/[email protected], Linux/Linux@afca229b39acc2590976b3e4f6e0fe76cededc60 · CNA
  4. 2026-10-16 1 new reference · CNA
  5. 2026-10-19 Fix available: Linux/[email protected] · CNA
  6. 2026-10-21 Fix available: Linux/Linux@0e3e3cec28c4d1bf29948da40b4e9e5d44f7852b, Linux/Linux@49d7e1b456ba2f3ee08b3e264d999c09992cde8e, Linux/[email protected] +1 · CNA
  7. 2026-10-21 2 new references · CNA
  8. 2026-10-28 CVSS score added · NVD
  9. 2026-10-28 Weakness changed · NVD
  10. 2026-11-01 Affected versions changed · Red Hat
  11. 2026-11-01 CVSS score added · Red Hat

References

  • 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