CVE-2025-21795
NFSD: fix hang in nfsd4_shutdown_callback
At a glance
- Severity
- HIGH 7.5
- EPSS
- EPSS 0.67 % · percentile 52 (2026-10-27)
- State
- PUBLISHED
- Published
- Updated
- Assigner
- Linux
- NVD status
- Modified
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.
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | Linux |
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | NVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary) |
| CVSS 3.1 | MEDIUM 5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H | NVD · nvd@nist.gov (Primary) |
European references
- ENISA EUVD · EUVD-2025-5127
- GCVE · GCVE-0-2025-21795
CERT-FR advisories
- CERTFR-2026-AVI-1298 — Multiples vulnérabilités dans les produits Siemens · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0880 — Multiples vulnérabilités dans les produits Siemens · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0082 — Multiples vulnérabilités dans le noyau Linux de Red Hat · cert.ssi.gouv.fr
- CERTFR-2025-AVI-1057 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0969 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0758 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0743 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0721 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0559 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0509 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0492 — Multiples vulnérabilités dans les produits Siemens · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0463 — Multiples vulnérabilités dans le noyau Linux de Debian LTS · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0277 — Multiples vulnérabilités dans le noyau Linux de Debian LTS · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0234 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0212 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.10.220 < 5.10.235cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.15.154 < 5.15.179cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.19 < 6.1.129cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.2 < 6.6.79cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.7 < 6.12.16cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.13 < 6.13.4cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*
Affected products
| Product | Versions |
|---|---|
| Linux · Linux | affected 67ef9e5fd737eab2495f2586df7e9ea30caa1b77 < abed68027ea3ab893ac85cc46a00e2e64a324239 ; affected 26540b8940a2e21582afa61a6fb8af87310bac72 < efa8a261c575f816c7e79a87aeb3ef8a0bd6b221 ; affected 66af25799940b26efd41ea6e648f75c41a48a2c2 < 38d345f612503b850c2973e5a879f88e441b34d7 ; affected 66af25799940b26efd41ea6e648f75c41a48a2c2 < 23ad7797c74cd8f7f90617f1e59a8703e2b43908 ; affected 66af25799940b26efd41ea6e648f75c41a48a2c2 < cedfbb92cf97a6bff3d25633001d9c44442ee854 ; affected 66af25799940b26efd41ea6e648f75c41a48a2c2 < e88d2451cd42e025465d6b51fd716a47b0b3800d |
| Linux · Linux | affected 5.19 ; unaffected 0 < 5.19 ; unaffected 5.10.235 ≤ 5.10.* ; unaffected 5.15.179 ≤ 5.15.* ; unaffected 6.1.129 ≤ 6.1.* ; unaffected 6.6.79 ≤ 6.6.* |
References
- https://git.kernel.org/stable/c/abed68027ea3ab893ac85cc46a00e2e64a324239
- https://git.kernel.org/stable/c/efa8a261c575f816c7e79a87aeb3ef8a0bd6b221
- https://git.kernel.org/stable/c/38d345f612503b850c2973e5a879f88e441b34d7
- https://git.kernel.org/stable/c/23ad7797c74cd8f7f90617f1e59a8703e2b43908
- https://git.kernel.org/stable/c/cedfbb92cf97a6bff3d25633001d9c44442ee854
- https://git.kernel.org/stable/c/e88d2451cd42e025465d6b51fd716a47b0b3800d
- https://git.kernel.org/stable/c/036ac2778f7b28885814c6fbc07e156ad1624d03
- https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html
- https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html
- https://cert-portal.siemens.com/productcert/html/ssa-265688.html
- https://cert-portal.siemens.com/productcert/html/ssa-082556.html
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://cert-portal.siemens.com/productcert/html/ssa-457936.html
- https://cert-portal.siemens.com/productcert/html/ssa-784472.html
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |