CVE-2026-64253

In the Linux kernel, the following vulnerability has been resolved: kernel/fork: clear PF_BLOCK_TS in copy_process() PF_BLOCK_TS is only set in blk_time_get_ns() when current->plug is non-NULL, and blk_finish_plug() clears it via __blk_flush_plug() before NULLing the plug pointer. copy_process() breaks the invariant by inheriting PF_BLOCK_TS from the parent while resetting the child's plug to NULL. Clear PF_BLOCK_TS alongside that assignment so callers can rely on "PF_BLOCK_TS set implies current->plug != NULL" and dereference current->plug unguarded.

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/77bba61a20f1b3d206f4f90e10a7bb3cd90b9619	Patch
https://git.kernel.org/stable/c/99e6c712cc300883b8cbf03347d5359ec1a4d6dd	Patch
https://git.kernel.org/stable/c/ee0801aceabdf583392477baf69a290b09448b8f	Patch
https://git.kernel.org/stable/c/fd38b75c4b43295b10d69772a46d1c74dbd6fc81	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::::::::

History

No history.

Information

Published : 2026-07-24 16:16

Updated : 2026-08-17 05:17

NVD link : CVE-2026-64253

Mitre link : CVE-2026-64253

CVE.ORG link : CVE-2026-64253

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-476

NULL Pointer Dereference

{"id": "CVE-2026-64253", "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}]}, "affected": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "affectedData": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "06b23f92af87a84d70881b2ecaa72e00f7838264", "lessThan": "ee0801aceabdf583392477baf69a290b09448b8f", "versionType": "git"}, {"status": "affected", "version": "06b23f92af87a84d70881b2ecaa72e00f7838264", "lessThan": "99e6c712cc300883b8cbf03347d5359ec1a4d6dd", "versionType": "git"}, {"status": "affected", "version": "06b23f92af87a84d70881b2ecaa72e00f7838264", "lessThan": "77bba61a20f1b3d206f4f90e10a7bb3cd90b9619", "versionType": "git"}, {"status": "affected", "version": "06b23f92af87a84d70881b2ecaa72e00f7838264", "lessThan": "fd38b75c4b43295b10d69772a46d1c74dbd6fc81", "versionType": "git"}], "programFiles": ["kernel/fork.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "6.9"}, {"status": "unaffected", "version": "0", "lessThan": "6.9", "versionType": "semver"}, {"status": "unaffected", "version": "6.12.95", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.18.38", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "7.1.3", "versionType": "semver", "lessThanOrEqual": "7.1.*"}, {"status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["kernel/fork.c"], "defaultStatus": "affected"}]}], "published": "2026-07-24T16:16:55.017", "references": [{"url": "https://git.kernel.org/stable/c/77bba61a20f1b3d206f4f90e10a7bb3cd90b9619", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/99e6c712cc300883b8cbf03347d5359ec1a4d6dd", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/ee0801aceabdf583392477baf69a290b09448b8f", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/fd38b75c4b43295b10d69772a46d1c74dbd6fc81", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-476"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nkernel/fork: clear PF_BLOCK_TS in copy_process()\n\nPF_BLOCK_TS is only set in blk_time_get_ns() when current->plug is\nnon-NULL, and blk_finish_plug() clears it via __blk_flush_plug()\nbefore NULLing the plug pointer. copy_process() breaks the\ninvariant by inheriting PF_BLOCK_TS from the parent while resetting\nthe child's plug to NULL.\n\nClear PF_BLOCK_TS alongside that assignment so callers can rely on\n\"PF_BLOCK_TS set implies current->plug != NULL\" and dereference\ncurrent->plug unguarded."}], "lastModified": "2026-08-17T05:17:23.850", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "E08F80D6-87F6-4B96-A3A9-F172D7A2E3AA", "versionEndExcluding": "6.12.95", "versionStartIncluding": "6.9"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "FA591B28-5D62-449E-BDBE-3C9391BF070A", "versionEndExcluding": "6.18.38", "versionStartIncluding": "6.13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "9526B150-E2B3-4C6F-8AE5-1AF92B75AD9E", "versionEndExcluding": "7.1.3", "versionStartIncluding": "6.19"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}