CVE-2026-53271

{"id": "CVE-2026-53271", "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": "8df4bcdb0a4232192b2445256c39b787d58ef14d", "lessThan": "945a86b21b40fb17183f5b27461baa6f03e2467f", "versionType": "git"}, {"status": "affected", "version": "c8efcc786146a951091588e5fa7e3c754850cb3c", "lessThan": "1ff58dcfcab434ebb51649da33774fbb8e1f7b67", "versionType": "git"}, {"status": "affected", "version": "c8efcc786146a951091588e5fa7e3c754850cb3c", "lessThan": "e735dbd489e3ea02be78dba991056fe1138be51e", "versionType": "git"}, {"status": "affected", "version": "c8efcc786146a951091588e5fa7e3c754850cb3c", "lessThan": "75e33deda658c1ab3a9336cbdb1436536f9b3660", "versionType": "git"}, {"status": "affected", "version": "c8efcc786146a951091588e5fa7e3c754850cb3c", "lessThan": "b003086d76968298f22e7cf62239833b5a3a06b1", "versionType": "git"}, {"status": "affected", "version": "6.6.32", "lessThan": "6.6.143", "versionType": "semver"}], "programFiles": ["fs/smb/server/oplock.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": "6.6.143", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.94", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.18.36", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "7.0.13", "versionType": "semver", "lessThanOrEqual": "7.0.*"}, {"status": "unaffected", "version": "7.1", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["fs/smb/server/oplock.c"], "defaultStatus": "affected"}]}], "published": "2026-06-25T09:16:45.247", "references": [{"url": "https://git.kernel.org/stable/c/1ff58dcfcab434ebb51649da33774fbb8e1f7b67", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/75e33deda658c1ab3a9336cbdb1436536f9b3660", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/945a86b21b40fb17183f5b27461baa6f03e2467f", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/b003086d76968298f22e7cf62239833b5a3a06b1", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/e735dbd489e3ea02be78dba991056fe1138be51e", "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\nksmbd: fix NULL-deref of opinfo->conn in oplock/lease break notifiers\n\nsmb2_oplock_break_noti() and smb2_lease_break_noti() read opinfo->conn\ninto a local with neither READ_ONCE() nor a NULL check. Both run from\noplock_break() after opinfo_get_list() has dropped ci->m_lock, so a\nconcurrent SMB2 LOGOFF (session_fd_check()) can set op->conn = NULL\nunder ci->m_lock within that window. ksmbd_conn_r_count_inc(conn) then\nwrites through NULL at offset 0xc4 -- a remotely triggerable oops.\n\nGuard both reads the way compare_guid_key() already does: read\nopinfo->conn with READ_ONCE() and return early if it is NULL, before\nallocating the work struct so nothing leaks. A NULL conn means the\nclient is gone and the break is moot, so return 0; oplock_break() treats\nthat as success and runs the normal teardown."}], "lastModified": "2026-07-08T04:01:39.257", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4870AAED-882B-41F6-9339-0744EE085A78", "versionEndExcluding": "6.6.143", "versionStartIncluding": "6.6.32"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0FA23C34-76C0-4758-A17E-44FD25C1DEA5", "versionEndExcluding": "6.12.94", "versionStartIncluding": "6.9"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "389025D2-958D-41BD-BD96-70ED1033A9F3", "versionEndExcluding": "6.18.36", "versionStartIncluding": "6.13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "6A64BF9F-3BCA-42FD-98CB-8F03474D2B1E", "versionEndExcluding": "7.0.13", "versionStartIncluding": "6.19"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "B1EF7059-E670-45F4-B422-54C40FA86390"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0D38F0BF-A728-4133-A358-D44A2F7EE6D6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "EC732D08-5F7B-46D9-B154-E60C7F4F0A97"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "E5910A9D-F60A-409A-B486-FE66BFEBA9B9"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "81DFF19E-9CF8-49C6-8C36-1E4038622933"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "B0E8FC71-3952-444C-83E9-718DBBBEC615"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}