Medium [CVE-2026-89545] Linux kernel: Use-after-free in sunrpc due to asynchronous memory deallocation
This medium-severity Red Hat Linux advisory covers CVE-2026-89545.
Android app · Google Play
Monitor future Red Hat Linux CVEs from your phone.
Choose a whole vendor or a precise platform, then receive matching security advisories by phone notification, email, or both. Coverage follows 32 official vendor sources and 160+ reviewed platform categories.
Summary
A flaw was found in the Linux kernel. This vulnerability exists within the `sunrpc` component, where memory associated with `rq_argp` and `rq_resp` is freed prematurely.
Specifically, the `svc_rqst_free()` function frees these structures synchronously, while the main request structure (`rqstp`) is freed later via `kfree_rcu()`. This timing issue creates a window where RCU (Read-Copy-Update) readers can still access the already freed `rq_argp` and `rq_resp` pointers, leading to a use-after-free condition.
This memory corruption can result in system instability or potentially lead to further exploitation. Red Hat severity: Important — CVSS 6.6 (CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H).
Weakness: CWE-366.
Affected versions
No affected-version range was extracted from the source record. The vendor advisory is authoritative — check it before change work.
Official advisory · medium-confidence parse· fetched 2 hours ago·verify at source
Fixed versions
No fixed release is recorded yet. That does not prove no patch exists — confirm against the vendor advisory.
Official advisory · medium-confidence parse· fetched 2 hours ago·verify at source
Mitigation
The source record does not include mitigation steps. That is not a statement that no fix exists — read the vendor advisory below for the authoritative guidance.
Official advisory · medium-confidence parse· fetched 2 hours ago·verify at source
Discussion(0)
No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.
Sign in to join the discussion.