CVE-2025-39688

nfsd: allow SC_STATUS_FREEABLE when searching via nfs4_lookup_stateid()

MEDIUM
5.5
CVSS Score
Published: April 18, 2025 at 07:01 AM UTC
Updated: October 15, 2026 at 10:18 PM UTC
1 product affected across 1 vendorLinux Kernel

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Severity
MEDIUM5.5
Exploit prediction
EPSS 0.6%
SSVC
No known exploit

Description

In the Linux kernel, the following vulnerability has been resolved: nfsd: allow SC_STATUS_FREEABLE when searching via nfs4_lookup_stateid() The pynfs DELEG8 test fails when run against nfsd. It acquires a delegation and then lets the lease time out. It then tries to use the deleg stateid and expects to see NFS4ERR_DELEG_REVOKED, but it gets bad NFS4ERR_BAD_STATEID instead. When a delegation is revoked, it's initially marked with SC_STATUS_REVOKED, or SC_STATUS_ADMIN_REVOKED and later, it's marked with the SC_STATUS_FREEABLE flag, which denotes that it is waiting for s FREE_STATEID call. nfs4_lookup_stateid() accepts a statusmask that includes the status flags that a found stateid is allowed to have. Currently, that mask never includes SC_STATUS_FREEABLE, which means that revoked delegations are (almost) never found. Add SC_STATUS_FREEABLE to the always-allowed status flags, and remove it from nfsd4_delegreturn() since it's now always implied.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

6.11.6 ≤ v < 6.126.12.1 ≤ v < 6.12.236.13 ≤ v < 6.13.116.14 ≤ v < 6.14.26.11.66.126.12 rc56.12 rc66.12 rc78dd91e8d31febf4d9cca3ae1bb4771d33ae7ee5a967faa26f313a62e7bebc55d5b8122eaee43b929
Vendor states this is fixed in 52e209203c35a4fbff8af23cd3613efe5df40102 (fixed)
Vendor states this is fixed in 5bcb44e650bc4ec7eac23df90c5e011a77fa2beb (fixed)
Vendor states this is fixed in d1bc15b147d35b4cb7ca99a9a7d79d41ca342c13 (fixed)
Vendor states this is fixed in dc6f3295905d7185e71091870119a8c11c3808cc (fixed)
Vendor states this is fixed in 6.12 (unaffected)
Vendor states this is fixed in 6.12.23 (unaffected)
Vendor states this is fixed in 6.13.11 (unaffected)
Vendor states this is fixed in 6.14.2 (unaffected)
Vendor states this is fixed in 6.15 (unaffected)

References (4)

Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/52e209203c35a4fbff8af23cd3613efe5df40102
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/5bcb44e650bc4ec7eac23df90c5e011a77fa2beb
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/d1bc15b147d35b4cb7ca99a9a7d79d41ca342c13
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/dc6f3295905d7185e71091870119a8c11c3808cc

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
LOCAL
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
NVD-CWE-noinfo

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