CVE-2025-38588
Published: August 20, 2025Last modified: August 20, 2025
Description
In the Linux kernel, the following vulnerability has been resolved: ipv6: prevent infinite loop in rt6_nlmsg_size() While testing prior patch, I was able to trigger an infinite loop in rt6_nlmsg_size() in the following place: list_for_each_entry_rcu(sibling, &f6i->fib6_siblings, fib6_siblings) { rt6_nh_nlmsg_size(sibling->fib6_nh, &nexthop_len); } This is because fib6_del_route() and fib6_add_rt2node() uses list_del_rcu(), which can confuse rcu readers, because they might no longer see the head of the list. Restart the loop if f6i->fib6_nsiblings is zero.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 5.5 |
| Attack Vector | LOCAL |
| Attack complexity | LOW |
| Privileges required | LOW |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | NONE |
| Integrity impact | NONE |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Fixed (6.1.151-r0) |
| 25 LTS | linux-lts | Not affected (6.6.89-r0) | |
| Stream | linux-lts | Not affected (6.1.33-r0) |
References
- https://git.kernel.org/stable/c/3c13db3e47e170bab19e574404e7b6be45ea873d
- https://git.kernel.org/stable/c/46aeb66e9e54ed0d56c18615e1c3dbd502b327ab
- https://git.kernel.org/stable/c/54e6fe9dd3b0e7c481c2228782c9494d653546da
- https://git.kernel.org/stable/c/6d345136c9b875f065d226908a29c25cdf9343f8
- https://git.kernel.org/stable/c/cd8d8bbd9ced4cc5d06d858f67d4aa87745e8f38
- https://git.kernel.org/stable/c/e1b7932af47f92432be8303d2439d1bf77b0be23
- https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html