CVE-2026-63867

{"id": "CVE-2026-63867", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-63867", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-10-16T15:32:35.077407Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 8.2, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H", "integrityImpact": "LOW", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 4.2, "exploitabilityScore": 3.9}]}, "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": "fa3fe2b150316b294f2c662653501273ff25bba8", "lessThan": "301a33fd590c408a05c5df800e0cc1e6a8a2f8f8", "versionType": "git"}, {"status": "affected", "version": "fa3fe2b150316b294f2c662653501273ff25bba8", "lessThan": "68364963e5baf03f16b4420292291f75c8f66497", "versionType": "git"}, {"status": "affected", "version": "fa3fe2b150316b294f2c662653501273ff25bba8", "lessThan": "907ac6b1658e0277f979fcdfae2a753b495c1510", "versionType": "git"}, {"status": "affected", "version": "fa3fe2b150316b294f2c662653501273ff25bba8", "lessThan": "c4f4cf60797974873dbc8e100144682a6f2f861f", "versionType": "git"}, {"status": "affected", "version": "fa3fe2b150316b294f2c662653501273ff25bba8", "lessThan": "3b8cbba7c0ed31189c89f90be247b8973ffa79ef", "versionType": "git"}, {"status": "affected", "version": "fa3fe2b150316b294f2c662653501273ff25bba8", "lessThan": "8f4f0a157e8436a05bf8c3670b24dbc258911c43", "versionType": "git"}, {"status": "affected", "version": "fa3fe2b150316b294f2c662653501273ff25bba8", "lessThan": "8ab24fdebc369c0dfb90f82c1650b1e66662bb45", "versionType": "git"}], "programFiles": ["net/mptcp/options.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "5.11"}, {"status": "unaffected", "version": "0", "lessThan": "5.11", "versionType": "semver"}, {"status": "unaffected", "version": "5.15.210", "versionType": "semver", "lessThanOrEqual": "5.15.*"}, {"status": "unaffected", "version": "6.1.176", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"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": ["net/mptcp/options.c"], "defaultStatus": "affected"}]}], "published": "2026-07-19T15:16:53.617", "references": [{"url": "https://git.kernel.org/stable/c/301a33fd590c408a05c5df800e0cc1e6a8a2f8f8", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/3b8cbba7c0ed31189c89f90be247b8973ffa79ef", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/68364963e5baf03f16b4420292291f75c8f66497", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/8ab24fdebc369c0dfb90f82c1650b1e66662bb45", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/8f4f0a157e8436a05bf8c3670b24dbc258911c43", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/907ac6b1658e0277f979fcdfae2a753b495c1510", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/c4f4cf60797974873dbc8e100144682a6f2f861f", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-367"}]}, {"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-362"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: close TOCTOU race while computing rcv_wnd\n\nThe MPTCP output path access locklessly the MPTCP-level ack_seq\nin multiple times, using possibly different values for the data_ack\nin the DSS option and to compute the announced rcv wnd for the same\npacket.\n\nRefactor the cote to avoid inconsistencies which may confuse the\npeer. Also ensure that the MPTCP level rcv wnd is updated only when\nthe egress packet actually contains a DSS ack."}], "lastModified": "2026-10-26T16:49:22.910", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "5E938CDF-D1C4-43D0-98DC-9E11B6B55801", "versionEndExcluding": "5.15.210", "versionStartIncluding": "5.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "C4446623-5F2B-4DD8-8666-9FAAC285A757", "versionEndExcluding": "6.1.176", "versionStartIncluding": "5.16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "9062F1CD-CAD6-4EA2-A73F-C06D4A887B8C", "versionEndExcluding": "6.6.143", "versionStartIncluding": "6.2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "85421C0C-ABDE-4357-971C-67F9087DE1B9", "versionEndExcluding": "6.12.94", "versionStartIncluding": "6.7"}, {"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"}