CVE-2025-38588: Debian Linux

Medium severity, CVSS 5.5. EPSS: 0.2% chance of exploitation in the next 30 days.

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.

Affected products

• Debian Debian Linux: version 11.0 only
• Linux Linux Kernel: from 6.1.128, before 6.1.148 (fixed in 6.1.148); from 6.6.75, before 6.6.102 (fixed in 6.6.102); from 6.11.11, before 6.12 (fixed in 6.12); from 6.12.2, before 6.12.42 (fixed in 6.12.42); from 6.13, before 6.15.10 (fixed in 6.15.10); from 6.16, before 6.16.1 (fixed in 6.16.1)

Published 2025-08-19. Last modified 2026-06-17.