CVE-2025-21795
Description
In the Linux kernel, the following vulnerability has been resolved: NFSD: fix hang in nfsd4_shutdown_callback If nfs4_client is in courtesy state then there is no point to send the callback. This causes nfsd4_shutdown_callback to hang since cl_cb_inflight is not 0. This hang lasts about 15 minutes until TCP notifies NFSD that the connection was dropped. This patch modifies nfsd4_run_cb_work to skip the RPC call if nfs4_client is in courtesy state.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or โ if you've already worked around this in production โ publish your fix to the community-verified tier.
โ Propose a mitigation on Community โ Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| rhel | 9 | fixed | |
| sles | affected | | |
| rocky | 9 | fixed | |
| debian | bookworm | fixed | 6.1.129-1 |
| debian | bullseye | fixed | 5.10.237-1 |
| debian | forky | fixed | 6.12.16-1 |
| debian | sid | fixed | 6.12.16-1 |
| debian | trixie | fixed | 6.12.16-1 |
| linux-kernel | affected | 5.10.235 | |
| linux-kernel | 6.14 | affected | |
| almalinux | 9 | fixed | kernel-doc-5.14.0-611.5.1.el9_7.noarch.rpm |
References
- https://access.redhat.com/errata/RHSA-2025:20518
- https://git.kernel.org/stable/c/036ac2778f7b28885814c6fbc07e156ad1624d03
- https://git.kernel.org/stable/c/23ad7797c74cd8f7f90617f1e59a8703e2b43908
- https://git.kernel.org/stable/c/38d345f612503b850c2973e5a879f88e441b34d7
- https://git.kernel.org/stable/c/abed68027ea3ab893ac85cc46a00e2e64a324239
- https://git.kernel.org/stable/c/cedfbb92cf97a6bff3d25633001d9c44442ee854
- https://git.kernel.org/stable/c/e88d2451cd42e025465d6b51fd716a47b0b3800d
- https://git.kernel.org/stable/c/efa8a261c575f816c7e79a87aeb3ef8a0bd6b221
- https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html
- https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html
- https://cert-portal.siemens.com/productcert/html/ssa-082556.html
- https://cert-portal.siemens.com/productcert/html/ssa-265688.html
- https://www.suse.com/security/cve/CVE-2025-21795.html
- https://errata.rockylinux.org/RLSA-2025:20518
- https://security-tracker.debian.org/tracker/CVE-2025-21795
- https://bugzilla.redhat.com/2298169
- https://bugzilla.redhat.com/2312077
- https://bugzilla.redhat.com/2313092
- https://bugzilla.redhat.com/2320172
- https://bugzilla.redhat.com/2320259
- https://bugzilla.redhat.com/2320455
- https://bugzilla.redhat.com/2320616
- https://bugzilla.redhat.com/2320722
- https://bugzilla.redhat.com/2324549
- https://bugzilla.redhat.com/2327203
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.