CVE-2026-89671: nfsd: gate nfs3 setacl by argp->mask
- Is it exploited?
Not on CISA's list. CISA has not added it to the Known Exploited Vulnerabilities catalog as of . If CISA adds it, this page shows it as known exploited.
- How likely is exploitation in the next 30 days?
- 0.5%
EPSS score, percentile 42.8 of all scored records. A probability estimated by FIRST, not a report of exploitation.
- How severe?
- 9.1 Critical
CVSS v3.1 base score, given by the CNA
- What should I do?
CISA has set no required action, because the vulnerability is not in KEV.
The CVE record links no vendor advisory, patch or mitigation.
- Which versions are affected?
Affected
- 2.6.13
Unaffected before 2.6.13; 6.6.157; 6.12.109; 6.18.50; 7.2.4; 7.3
Source: CISA KEV 2026.10.28, as of ; FIRST EPSS, as of ; CVE List, as of . About the data.
What to do
Advisories and patches
The CVE record links no vendor advisory, patch or mitigation.
This summary is based on the CVE record as of . Check the vendor's advisory before you act: affected versions and fixes can change.
Affected products and versions
As listed in the CVE record.
| Status | Versions |
|---|---|
| Affected | from a257cdd0e217 to before 3be1d8611dae |
| Affected | from a257cdd0e217 to before 68a80b26efdf |
| Affected | from a257cdd0e217 to before b3bff820d068 |
| Affected | from a257cdd0e217 to before ff99ed007f06 |
| Affected | from a257cdd0e217 to before 453d7198a0ab |
Versions not listed are: unaffected.
| Status | Versions |
|---|---|
| Affected | 2.6.13 |
| Unaffected | before 2.6.13 |
| Unaffected | 6.6.157 |
| Unaffected | 6.12.109 |
| Unaffected | 6.18.50 |
| Unaffected | 7.2.4 |
| Unaffected | 7.3 |
Versions not listed are: affected.
Versions the record lists as unaffected: 6.6.157, 6.12.109, 6.18.50, 7.2.4, 7.3.
Source: CVE List, as of . About the data.
About this vulnerability
In the Linux kernel, the following vulnerability has been resolved: nfsd: gate nfs3 setacl by argp->mask nfsd3_proc_setacl() calls set_posix_acl() unconditionally for both ACL_TYPE_ACCESS and ACL_TYPE_DEFAULT, passing argp->acl_access and argp->acl_default verbatim. The NFSv3 ACL decoder only populates those pointers when the corresponding mask bit is set: nfs3svc_decode_setaclargs()…
Summary: CVE record, as of .
- CISA has not added CVE-2026-89671 to its Known Exploited Vulnerabilities (KEV) catalog, as of 28 Oct 2026.
- The CVE record was published on 11 Sep 2026.
- The CVE record carries a CVSS v3.1 base score of 9.1 (Critical), given by its CNA.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 0.5% (percentile 42.8), as of 29 Oct 2026. EPSS is a statistical estimate, not a report of exploitation.
- CISA's SSVC assessment in the CVE record: exploitation none, automatable yes, technical impact total.
Source: CISA KEV 2026.10.28, as of ; CVE List, as of ; FIRST EPSS, as of . About the data.
Description
nfsd: gate nfs3 setacl by argp->mask
In the Linux kernel, the following vulnerability has been resolved: nfsd: gate nfs3 setacl by argp->mask nfsd3_proc_setacl() calls set_posix_acl() unconditionally for both ACL_TYPE_ACCESS and ACL_TYPE_DEFAULT, passing argp->acl_access and argp->acl_default verbatim. The NFSv3 ACL decoder only populates those pointers when the corresponding mask bit is set: nfs3svc_decode_setaclargs() if (args->mask & NFS_ACL) decode into acl_access if (args->mask & NFS_DFACL) decode into acl_default /* otherwise the pointer stays NULL (pc_argzero) */ nfsd3_proc_setacl() set_posix_acl(.., ACL_TYPE_ACCESS, argp->acl_access) set_posix_acl(.., ACL_TYPE_DEFAULT, argp->acl_default) set_posix_acl(idmap, dentry, type, NULL) is the VFS "remove this ACL type" operation. A NULL pointer that means "the client did not send this arm" is therefore indistinguishable from "the client asked to remove this ACL". A SETACL with mask=NFS_ACL silently drops the directory's default ACL; mask=0 drops both. The sibling nfsd3_proc_getacl() already consults argp->mask before touching each arm; mirror that in setacl. Fix by wrapping each set_posix_acl() call in the matching mask bit check and initializing error to 0 before inode_lock so that a request with neither bit set leaves the on-disk ACLs untouched and returns nfs_ok. The out_drop_lock path and the unconditional posix_acl_release() at out: are preserved; both NULL-tolerate the skipped arms.
Source: CVE List, as of . About the data.
Timeline
| Date | Event |
|---|---|
| CVE record published | |
| CVE record last updated |
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