CVE-2025-38477: Debian Linux

Medium severity, CVSS 4.7. EPSS: 0.1% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_qfq: Fix race condition on qfq_aggregate A race condition can occur when 'agg' is modified in qfq_change_agg (called during qfq_enqueue) while other threads access it concurrently. For example, qfq_dump_class may trigger a NULL dereference, and qfq_delete_class may cause a use-after-free. This patch addresses the issue by: 1. Moved qfq_destroy_class into the critical section. 2. Added sch_tree_lock protection to qfq_dump_class and qfq_dump_class_stats.

Affected products

• Debian Debian Linux: version 11.0 only
• Linux Linux Kernel: from 3.8, before 5.4.297 (fixed in 5.4.297); from 5.5, before 5.10.241 (fixed in 5.10.241); from 5.11, before 5.15.190 (fixed in 5.15.190); from 5.16, before 6.1.147 (fixed in 6.1.147); from 6.2, before 6.6.100 (fixed in 6.6.100); from 6.7, before 6.12.40 (fixed in 6.12.40); …

Published 2025-07-28. Last modified 2026-07-30.