CVE-2025-21641

In the Linux kernel, the following vulnerability has been resolved: mptcp: sysctl: blackhole timeout: avoid using current->nsproxy As mentioned in the previous commit, using the 'net' structure via 'current' is not recommended for different reasons: - Inconsistency: getting info from the reader's/writer's netns vs only from the opener's netns. - current->nsproxy can be NULL in some cases, resulting in an 'Oops' (null-ptr-deref), e.g. when the current task is exiting, as spotted by syzbot [1] using acct(2). The 'pernet' structure can be obtained from the table->data using container_of().

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/4c74fbdc5ab95b13945be01e6065940b68222db7	Mailing List Patch
https://git.kernel.org/stable/c/92cf7a51bdae24a32c592adcdd59a773ae149289	Mailing List Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:6.13:rc1::::::
	cpe:2.3:o:linux:linux_kernel:6.13:rc2::::::
	cpe:2.3:o:linux:linux_kernel:6.13:rc3::::::
	cpe:2.3:o:linux:linux_kernel:6.13:rc4::::::
	cpe:2.3:o:linux:linux_kernel:6.13:rc5::::::
	cpe:2.3:o:linux:linux_kernel:6.13:rc6::::::

History

No history.

Information

Published : 2025-01-19 11:15

Updated : 2025-10-01 20:18

NVD link : CVE-2025-21641

Mitre link : CVE-2025-21641

CVE.ORG link : CVE-2025-21641

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-476

NULL Pointer Dereference

{"id": "CVE-2025-21641", "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}, {"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "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": "2025-01-19T11:15:09.643", "references": [{"url": "https://git.kernel.org/stable/c/4c74fbdc5ab95b13945be01e6065940b68222db7", "tags": ["Mailing List", "Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/92cf7a51bdae24a32c592adcdd59a773ae149289", "tags": ["Mailing List", "Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-476"}]}, {"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-476"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: sysctl: blackhole timeout: avoid using current->nsproxy\n\nAs mentioned in the previous commit, using the 'net' structure via\n'current' is not recommended for different reasons:\n\n- Inconsistency: getting info from the reader's/writer's netns vs only\n from the opener's netns.\n\n- current->nsproxy can be NULL in some cases, resulting in an 'Oops'\n (null-ptr-deref), e.g. when the current task is exiting, as spotted by\n syzbot [1] using acct(2).\n\nThe 'pernet' structure can be obtained from the table->data using\ncontainer_of()."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: mptcp: sysctl: blackhole timeout: avoid using current->nsproxy Como se mencion\u00f3 en el commit anterior, no se recomienda usar la estructura 'net' a trav\u00e9s de 'current' por diferentes razones: - Inconsistencia: obtener informaci\u00f3n de las redes de red del lector/escritor frente a solo de las redes de red del abridor. - current->nsproxy puede ser NULL en algunos casos, lo que resulta en un 'Oops' (null-ptr-deref), por ejemplo, cuando la tarea actual est\u00e1 saliendo, como lo detect\u00f3 syzbot [1] usando acct(2). La estructura 'pernet' se puede obtener de table->data usando Container_of()."}], "lastModified": "2025-10-01T20:18:16.050", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "CAA666EC-CF76-46C6-AE86-951E128D4C0A", "versionEndExcluding": "6.12.10", "versionStartIncluding": "6.12"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "62567B3C-6CEE-46D0-BC2E-B3717FBF7D13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "5A073481-106D-4B15-B4C7-FB0213B8E1D4"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc3:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "DE491969-75AE-4A6B-9A58-8FC5AF98798F"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc4:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "93C0660D-7FB8-4FBA-892A-B064BA71E49E"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc5:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "034C36A6-C481-41F3-AE9A-D116E5BE6895"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc6:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "8AF9DC49-2085-4FFB-A7E3-73DFAFECC7F2"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}