CVE-2025-38108
Medium
Elevated severity or exploit probability.
CVSS breakdown
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
| Attack Vector | L | Local |
| Attack Complexity | L | Low |
| Privileges Required | L | Low |
| User Interaction | N | None |
| Scope | U | Unchanged |
| Confidentiality | H | High |
| Integrity | H | High |
| Availability | H | High |
Timeline
- 2025-07-03 — Published (NVD)
- 2026-07-30 — Last modified (NVD)
Description
In the Linux kernel, the following vulnerability has been resolved: net_sched: red: fix a race in __red_change() Gerrard Tai reported a race condition in RED, whenever SFQ perturb timer fires at the wrong time. The race is as follows: CPU 0 CPU 1 [1]: lock root [2]: qdisc_tree_flush_backlog() [3]: unlock root | | [5]: lock root | [6]: rehash | [7]: qdisc_tree_reduce_backlog() | [4]: qdisc_put() This can be abused to underflow a parent's qlen. Calling qdisc_purge_queue() instead of qdisc_tree_flush_backlog() should fix the race, because all packets will be purged from the qdisc before releasing the lock.
Affected
References
- https://git.kernel.org/stable/c/110a47efcf23438ff8d31dbd9c854fae2a48bf98
- https://git.kernel.org/stable/c/2790c4ec481be45a80948d059cd7c9a06bc37493
- https://git.kernel.org/stable/c/2a71924ca4af59ffc00f0444732b6cd54b153d0e
- https://git.kernel.org/stable/c/444ad445df5496a785705019268a8a84b84484bb
- https://git.kernel.org/stable/c/4b755305b2b0618e857fdadb499365b5f2e478d1
- https://git.kernel.org/stable/c/85a3e0ede38450ea3053b8c45d28cf55208409b8
- https://git.kernel.org/stable/c/a1bf6a4e9264a685b0e642994031f9c5aad72414
- https://git.kernel.org/stable/c/f569984417a4e12c67366e69bdcb752970de921d
- https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html
- https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html