Ubuntu Linux 6.8 GA retains the legacy AF_UNIX garbage collector but backports upstream commit 8594d9b85c07 ("af_unix: Don’t call skb_get() for OOB skb"). When orphaned MSG_OOB sockets hit unix_gc(), the garbage collector still calls kfree_skb() as if OOB SKBs held two references; on Ubuntu Linux 6.8 (Noble Numbat) kernel tree, they have only the queue reference, so the buffer is freed while still reachable and subsequent queue walks dereference freed memory, yielding a reliable local privilege escalation (LPE) caused by a use-after-free (UAF). Ubuntu builds that have already taken the new GC stack from commit 4090fa373f0e, and mainline Linux kernels shipping that infrastructure are unaffected because they no longer execute the legacy collector path. This issue affects Ubuntu Linux from 6.8.0-56.58 before 6.8.0-84.84.
Metrics
Affected Vendors & Products
References
History
Thu, 05 Mar 2026 21:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
Thu, 05 Mar 2026 19:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Ubuntu Linux 6.8 GA retains the legacy AF_UNIX garbage collector but backports upstream commit 8594d9b85c07 ("af_unix: Don’t call skb_get() for OOB skb"). When orphaned MSG_OOB sockets hit unix_gc(), the garbage collector still calls kfree_skb() as if OOB SKBs held two references; on Ubuntu Linux 6.8 (Noble Numbat) kernel tree, they have only the queue reference, so the buffer is freed while still reachable and subsequent queue walks dereference freed memory, yielding a reliable local privilege escalation (LPE) caused by a use-after-free (UAF). Ubuntu builds that have already taken the new GC stack from commit 4090fa373f0e, and mainline Linux kernels shipping that infrastructure are unaffected because they no longer execute the legacy collector path. This issue affects Ubuntu Linux from 6.8.0-56.58 before 6.8.0-84.84. | |
| Title | Use-after-free of orphaned AF_UNIX in Ubuntu builds of Linux kernel | |
| Weaknesses | CWE-416 | |
| References |
| |
| Metrics |
cvssV4_0
|
Status: PUBLISHED
Assigner: canonical
Published:
Updated: 2026-03-05T20:11:41.411Z
Reserved: 2025-11-18T09:33:14.643Z
Link: CVE-2025-13350
No data.
Status : Received
Published: 2026-03-05T20:16:10.730
Modified: 2026-03-05T21:16:12.963
Link: CVE-2025-13350
No data.
OpenCVE Enrichment
No data.