CVE-2026-63968ipv6: fix possible infinite loop in fib6_select_path()
Updated under an hour ago ()
Does this affect you?
It affects Linux. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
Do this next
Free account, 1 product
In the Linux kernel, the following vulnerability has been resolved: ipv6: fix possible infinite loop in fib6_select_path() Found while auditing the same pattern Sashiko reported in rt6_fill_node() [1]. Apply the same fix as commit f8d8ce1b515a ("ipv6: fix possible infinite loop in fib6_info_uses_dev()"). Writers holding tb6_lock can list_del_rcu(&first->fib6_siblings) without waiting for RCU readers; first->fib6_siblings.next then still points into the old ring and this softirq-side walker never reaches &first->fib6_siblings as its terminator. fib6_purge_rt() always WRITE_ONCE()s first->fib6_nsiblings to 0 before list_del_rcu(), so an inside-loop check is a reliable detach signal. [1] https://sashiko.dev/#/patchset/20260526020227.4857-1-jiayuan.chen%40linux.dev
- CVSS
- 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Weakness (CWE)
- Not given
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- Linux
- NVD analysis
- Awaiting Analysis
- Record last updated
- Oct 16, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Linux Linux linux:linux (from the name) | from d0ec61c9f3583b76aebdbb271f5c0d3fcccd48b2 before 3948a7d92f7678e89e1776bb2d169afcad63b1ae; from 52da02521ede55fb86546c3fffd9377b3261b91f before c87cd3cb309634bc8f50a54e2079424f219ac21f; 34a949e7a0869dfa31a40416d2a56973fae1807b builds before 0f7b73c3452635de83b8711b31abdda8e49aad7b; from d9ccb18f83ea2bb654289b6ecf014fd267cc988b before ab9a10969a907b472a0196d999c08ff7144172e3; from d9ccb18f83ea2bb654289b6ecf014fd267cc988b before 9b9d5bd6e3d4c9cecab5407604b690684b2532d2; from d9ccb18f83ea2bb654289b6ecf014fd267cc988b before 9c7da87c2dc860bb17ca1ece942495d28b1ce3b9; 11edcd026012ac18acee0f1514db3ed1b160fc6f; from 6.1.128 before 6.1.176; and 3 more ranges | CNA record |
References
- https://git.kernel.org/stable/c/3948a7d92f7678e89e1776bb2d169afcad63b1ae
- https://git.kernel.org/stable/c/c87cd3cb309634bc8f50a54e2079424f219ac21f
- https://git.kernel.org/stable/c/0f7b73c3452635de83b8711b31abdda8e49aad7b
- https://git.kernel.org/stable/c/ab9a10969a907b472a0196d999c08ff7144172e3
- https://git.kernel.org/stable/c/9b9d5bd6e3d4c9cecab5407604b690684b2532d2
- https://git.kernel.org/stable/c/9c7da87c2dc860bb17ca1ece942495d28b1ce3b9
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.