{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-53587", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-06-09T19:11:53.484Z", "datePublished": "2026-08-20T18:36:43.055Z", "dateUpdated": "2026-08-20T19:18:33.821Z"}, "containers": {"cna": {"title": "libgit2 - Unauthenticated network-reachable heap out-of-bounds read in transports/smart_pkt.c:set_data", "problemTypes": [{"descriptions": [{"cweId": "CWE-20", "lang": "en", "description": "CWE-20: Improper Input Validation", "type": "CWE"}]}, {"descriptions": [{"cweId": "CWE-125", "lang": "en", "description": "CWE-125: Out-of-bounds Read", "type": "CWE"}]}, {"descriptions": [{"cweId": "CWE-126", "lang": "en", "description": "CWE-126: Buffer Over-read", "type": "CWE"}]}, {"descriptions": [{"cweId": "CWE-1284", "lang": "en", "description": "CWE-1284: Improper Validation of Specified Quantity in Input", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}}], "references": [{"name": "https://github.com/libgit2/libgit2/security/advisories/GHSA-pm24-4jhq-3xvm", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/libgit2/libgit2/security/advisories/GHSA-pm24-4jhq-3xvm"}, {"name": "https://github.com/libgit2/libgit2/commit/2c0ce8c0132ac38ab0db28239462a671e2e5440e", "tags": ["x_refsource_MISC"], "url": "https://github.com/libgit2/libgit2/commit/2c0ce8c0132ac38ab0db28239462a671e2e5440e"}, {"name": "https://github.com/libgit2/libgit2/commit/affda60c10fcef16723451c0d7dc71b71dc20ad3", "tags": ["x_refsource_MISC"], "url": "https://github.com/libgit2/libgit2/commit/affda60c10fcef16723451c0d7dc71b71dc20ad3"}, {"name": "https://github.com/libgit2/libgit2/commit/d7a9fb87f504434e9f45228678953c4fa56e7640", "tags": ["x_refsource_MISC"], "url": "https://github.com/libgit2/libgit2/commit/d7a9fb87f504434e9f45228678953c4fa56e7640"}, {"name": "https://github.com/libgit2/libgit2/releases/tag/v1.8.6", "tags": ["x_refsource_MISC"], "url": "https://github.com/libgit2/libgit2/releases/tag/v1.8.6"}, {"name": "https://github.com/libgit2/libgit2/releases/tag/v1.9.5", "tags": ["x_refsource_MISC"], "url": "https://github.com/libgit2/libgit2/releases/tag/v1.9.5"}], "affected": [{"vendor": "libgit2", "product": "libgit2", "versions": [{"version": "< 1.8.6", "status": "affected"}, {"version": ">= 1.9.0, < 1.9.5", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-08-20T18:36:43.055Z"}, "descriptions": [{"lang": "en", "value": "libgit2 is a portable C implementation of the Git core methods provided as a linkable library with a solid API, allowing to build Git functionality into your application. Prior to 1.8.6 and 1.9.5, libgit2 performs a fixed-size strncmp in set_data in src/libgit2/transports/smart_pkt.c without first verifying that the smart-protocol pkt-line capability buffer contains 14 bytes. A malicious Git server can make bytes after the pkt-line complete object-format=, causing format_str to advance beyond the pkt-line and the following memchr length calculation to underflow. The resulting heap out-of-bounds walk can crash a client during the first refs-advertisement packet over HTTP, HTTPS, SSH, or the Git protocol. This issue is fixed in versions 1.8.6 and 1.9.5."}], "source": {"advisory": "GHSA-pm24-4jhq-3xvm", "discovery": "UNKNOWN"}}, "adp": [{"references": [{"url": "https://github.com/libgit2/libgit2/security/advisories/GHSA-pm24-4jhq-3xvm", "tags": ["exploit"]}], "metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-08-20T19:18:28.320266Z", "id": "CVE-2026-53587", "options": [{"Exploitation": "poc"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-08-20T19:18:33.821Z"}}]}}

{}

{"affected": [{"affectedData": [{"product": "libgit2", "vendor": "libgit2", "versions": [{"status": "affected", "version": "< 1.8.6"}, {"status": "affected", "version": ">= 1.9.0, < 1.9.5"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "libgit2 is a portable C implementation of the Git core methods provided as a linkable library with a solid API, allowing to build Git functionality into your application. Prior to 1.8.6 and 1.9.5, libgit2 performs a fixed-size strncmp in set_data in src/libgit2/transports/smart_pkt.c without first verifying that the smart-protocol pkt-line capability buffer contains 14 bytes. A malicious Git server can make bytes after the pkt-line complete object-format=, causing format_str to advance beyond the pkt-line and the following memchr length calculation to underflow. The resulting heap out-of-bounds walk can crash a client during the first refs-advertisement packet over HTTP, HTTPS, SSH, or the Git protocol. This issue is fixed in versions 1.8.6 and 1.9.5."}], "id": "CVE-2026-53587", "lastModified": "2026-08-20T19:16:55.137", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-08-20T19:16:55.137", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/libgit2/libgit2/commit/2c0ce8c0132ac38ab0db28239462a671e2e5440e"}, {"source": "security-advisories@github.com", "url": "https://github.com/libgit2/libgit2/commit/affda60c10fcef16723451c0d7dc71b71dc20ad3"}, {"source": "security-advisories@github.com", "url": "https://github.com/libgit2/libgit2/commit/d7a9fb87f504434e9f45228678953c4fa56e7640"}, {"source": "security-advisories@github.com", "url": "https://github.com/libgit2/libgit2/releases/tag/v1.8.6"}, {"source": "security-advisories@github.com", "url": "https://github.com/libgit2/libgit2/releases/tag/v1.9.5"}, {"source": "security-advisories@github.com", "url": "https://github.com/libgit2/libgit2/security/advisories/GHSA-pm24-4jhq-3xvm"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-20"}, {"lang": "en", "value": "CWE-125"}, {"lang": "en", "value": "CWE-126"}, {"lang": "en", "value": "CWE-1284"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{}