CVE-2025-39688

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.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/52e209203c35a4fbff8af23cd3613efe5df40102	Patch
https://git.kernel.org/stable/c/5bcb44e650bc4ec7eac23df90c5e011a77fa2beb	Patch
https://git.kernel.org/stable/c/d1bc15b147d35b4cb7ca99a9a7d79d41ca342c13	Patch
https://git.kernel.org/stable/c/dc6f3295905d7185e71091870119a8c11c3808cc	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:6.12:-::::::
	cpe:2.3:o:linux:linux_kernel:6.12:rc5::::::
	cpe:2.3:o:linux:linux_kernel:6.12:rc6::::::
	cpe:2.3:o:linux:linux_kernel:6.12:rc7::::::

History

No history.

Information

Published : 2025-04-18 07:15

Updated : 2025-11-06 21:34

NVD link : CVE-2025-39688

Mitre link : CVE-2025-39688

CVE.ORG link : CVE-2025-39688

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo

{"id": "CVE-2025-39688", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 1.8}]}, "published": "2025-04-18T07:15:43.937", "references": [{"url": "https://git.kernel.org/stable/c/52e209203c35a4fbff8af23cd3613efe5df40102", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/5bcb44e650bc4ec7eac23df90c5e011a77fa2beb", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/d1bc15b147d35b4cb7ca99a9a7d79d41ca342c13", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/dc6f3295905d7185e71091870119a8c11c3808cc", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: allow SC_STATUS_FREEABLE when searching via nfs4_lookup_stateid()\n\nThe pynfs DELEG8 test fails when run against nfsd. It acquires a\ndelegation and then lets the lease time out. It then tries to use the\ndeleg stateid and expects to see NFS4ERR_DELEG_REVOKED, but it gets\nbad NFS4ERR_BAD_STATEID instead.\n\nWhen a delegation is revoked, it's initially marked with\nSC_STATUS_REVOKED, or SC_STATUS_ADMIN_REVOKED and later, it's marked\nwith the SC_STATUS_FREEABLE flag, which denotes that it is waiting for\ns FREE_STATEID call.\n\nnfs4_lookup_stateid() accepts a statusmask that includes the status\nflags that a found stateid is allowed to have. Currently, that mask\nnever includes SC_STATUS_FREEABLE, which means that revoked delegations\nare (almost) never found.\n\nAdd SC_STATUS_FREEABLE to the always-allowed status flags, and remove it\nfrom nfsd4_delegreturn() since it's now always implied."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: nfsd: permite SC_STATUS_FREEABLE al buscar mediante nfs4_lookup_stateid() La prueba pynfs DELEG8 falla cuando se ejecuta contra nfsd. Adquiere una delegaci\u00f3n y luego deja que se agote el tiempo de concesi\u00f3n. Luego intenta usar el stateid de la deleg y espera ver NFS4ERR_DELEG_REVOKED, pero en su lugar obtiene NFS4ERR_BAD_STATEID incorrecto. Cuando se revoca una delegaci\u00f3n, inicialmente se marca con SC_STATUS_REVOKED o SC_STATUS_ADMIN_REVOKED y, m\u00e1s tarde, se marca con el indicador SC_STATUS_FREEABLE, que indica que est\u00e1 esperando una llamada FREE_STATEID. nfs4_lookup_stateid() acepta una m\u00e1scara de estado que incluye los indicadores de estado que se permite que tenga un stateid encontrado. Actualmente, esa m\u00e1scara nunca incluye SC_STATUS_FREEABLE, lo que significa que las delegaciones revocadas (casi) nunca se encuentran. Agregue SC_STATUS_FREEABLE a los indicadores de estado siempre permitidos y elim\u00ednelo de nfsd4_delegreturn(), ya que ahora siempre est\u00e1 impl\u00edcito."}], "lastModified": "2025-11-06T21:34:09.570", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "EC327455-C86D-4E78-8BC8-2E5301DD5835", "versionEndExcluding": "6.12", "versionStartIncluding": "6.11.6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "23274BE7-6B1D-4744-ADF5-6C2F83EC71A3", "versionEndExcluding": "6.12.23", "versionStartIncluding": "6.12.1"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "E7E864B0-8C00-4679-BA55-659B4C9C3AD3", "versionEndExcluding": "6.13.11", "versionStartIncluding": "6.13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "FADAE5D8-4808-442C-B218-77B2CE8780A0", "versionEndExcluding": "6.14.2", "versionStartIncluding": "6.14"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.12:-:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0E698080-7669-4132-8817-4C674EEBCE54"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.12:rc5:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "24DBE6C7-2AAE-4818-AED2-E131F153D2FA"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.12:rc6:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "24B88717-53F5-42AA-9B72-14C707639E3F"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.12:rc7:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "1EF8CD82-1EAE-4254-9545-F85AB94CF90F"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}