nfsd: reset write verifier on deferred writeback errors

MITRE NVD CVE.ORG JSON API

Summary

CVECVE-2026-53393
StatePUBLISHED
AssignerLinux
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-07-19 12:16:50 UTC
Updated2026-08-17 05:17:13 UTC
DescriptionIn the Linux kernel, the following vulnerability has been resolved: nfsd: reset write verifier on deferred writeback errors nfsd_vfs_write() and nfsd_commit() both call filemap_check_wb_err() to detect deferred writeback errors, but neither rotates the server's write verifier (nn->writeverf) when this check fails. Every other durable-storage-failure path in these functions calls commit_reset_write_verifier() before returning an error. The missing rotation means clients holding UNSTABLE write data under the current verifier will COMMIT, receive the unchanged verifier back, and conclude their data is durable — silently dropping data that failed writeback. This violates the UNSTABLE+COMMIT durability contract (RFC 1813 §3.3.7, RFC 8881 §18.32). Add commit_reset_write_verifier() calls at both filemap_check_wb_err() error sites, matching the pattern used by adjacent error paths in the same functions. The helper already filters -EAGAIN and -ESTALE internally, so the calls are unconditionally safe.

Risk And Classification

Primary CVSS: v3.1 5.5 MEDIUM from [email protected]

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS: 0.001770000 probability, percentile 0.074680000 (date 2026-07-29)

Problem Types: NVD-CWE-noinfo

CVSS v3.1 Breakdown

Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Operating System Linux Linux Kernel All All All All

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Linux Linux affected f14816f2f928c560d28ba344af689f56efcd6f55 b8e5894e56cff70fa245628fe16f0ad6367f8090 git Not specified
CNA Linux Linux affected 3145fe0ebb16e1715ad541a301bc6675c8375fcd bc2baca02ec56da7707a74ed5d340b0a1dff1841 git Not specified
CNA Linux Linux affected 555dbf1a9aac6d3150c8b52fa35f768a692f4eeb 43b65d2997963e80e8d8d86520bcb1e0751227de git Not specified
CNA Linux Linux affected 555dbf1a9aac6d3150c8b52fa35f768a692f4eeb 666e837b247fcadf2d8d508b9b0e49d720393eb4 git Not specified
CNA Linux Linux affected 555dbf1a9aac6d3150c8b52fa35f768a692f4eeb 1dd664b39774a9c89b72de8e59bf9ef4b3aaff2e git Not specified
CNA Linux Linux affected 555dbf1a9aac6d3150c8b52fa35f768a692f4eeb 4367afc119c51e17a616f6908772b7e2c2c4013f git Not specified
CNA Linux Linux affected 555dbf1a9aac6d3150c8b52fa35f768a692f4eeb b027cca33c97354149fcc0ddeede4525c41093cd git Not specified
CNA Linux Linux affected 555dbf1a9aac6d3150c8b52fa35f768a692f4eeb 2090b05803faab8a9fa62fbff871007862cac1b7 git Not specified
CNA Linux Linux affected 5.10.124 5.10.261 semver Not specified
CNA Linux Linux affected 5.15.49 5.15.212 semver Not specified
CNA Linux Linux affected 5.17 Not specified
CNA Linux Linux unaffected 5.17 semver Not specified
CNA Linux Linux unaffected 5.10.261 5.10.* semver Not specified
CNA Linux Linux unaffected 5.15.212 5.15.* semver Not specified
CNA Linux Linux unaffected 6.1.178 6.1.* semver Not specified
CNA Linux Linux unaffected 6.6.145 6.6.* semver Not specified
CNA Linux Linux unaffected 6.12.95 6.12.* semver Not specified
CNA Linux Linux unaffected 6.18.38 6.18.* semver Not specified
CNA Linux Linux unaffected 7.1.3 7.1.* semver Not specified
CNA Linux Linux unaffected 7.2 * original_commit_for_fix Not specified

References

ReferenceSourceLinkTags
git.kernel.org/stable/c/666e837b247fcadf2d8d508b9b0e49d720393eb4 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org Patch
git.kernel.org/stable/c/b8e5894e56cff70fa245628fe16f0ad6367f8090 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org Patch
git.kernel.org/stable/c/43b65d2997963e80e8d8d86520bcb1e0751227de 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org Patch
git.kernel.org/stable/c/4367afc119c51e17a616f6908772b7e2c2c4013f 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org Patch
git.kernel.org/stable/c/b027cca33c97354149fcc0ddeede4525c41093cd 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org Patch
git.kernel.org/stable/c/1dd664b39774a9c89b72de8e59bf9ef4b3aaff2e 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org Patch
git.kernel.org/stable/c/2090b05803faab8a9fa62fbff871007862cac1b7 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org Patch
git.kernel.org/stable/c/bc2baca02ec56da7707a74ed5d340b0a1dff1841 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org Patch
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

© CVE.report 2026

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report