{"id":"CVE-2026-91767","title":"php_openssl_matches_wildcard_name() in ext/openssl/xp_ssl.c underflows the length argument passed to memchr() when a TLS server certificate presents a wildcard name whose literal characters are together longer than the hostname being ver…","summary":"php_openssl_matches_wildcard_name() in ext/openssl/xp_ssl.c underflows the length argument passed to memchr() when a TLS server certificate presents a wildcard name whose literal characters are together longer than the hostname being ver…","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","cwe":["CWE-122","CWE-125"],"vendor":"PHP Group","product":"ext-openssl","affected":["ext-openssl >= 8.2.* < 8.2.34","ext-openssl >= 8.3.* < 8.3.35","ext-openssl >= 8.4.* < 8.4.26","ext-openssl >= 8.5.* < 8.5.11"],"patched":["hardened_images"],"published":"2026-09-25","updated":"2026-09-29","sourceUpdated":"2026-09-29T21:27:41.130","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-91767","references":[{"url":"https://github.com/php/php-src/security/advisories/GHSA-xr7j-rvgx-xq5p","label":"security@php.net"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-91767.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-91767"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2541652"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-91767"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-91767"},{"url":"https://access.redhat.com/errata/RHSA-2026:70720"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"epss":0.00105,"epssPercentile":0.01071,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-09-28T12:56:38.307648Z"},"ingestedAt":"2026-09-25T21:19:40.146Z","slug":"CVE-2026-91767","body":"## Overview\n\nphp_openssl_matches_wildcard_name() in ext/openssl/xp_ssl.c underflows the length argument passed to memchr() when a TLS server certificate presents a wildcard name whose literal characters are together longer than the hostname being verified. A malicious server presenting such a certificate makes the PHP client read up to SIZE_MAX bytes past the end of a heap allocation. The path is reachable from any default client stream, because verify_peer_name is enabled by default.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **RHSA-2026:70720** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-09-23 · [advisory](https://access.redhat.com/errata/RHSA-2026:70720)\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, … · updated 2026-10-14 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-91767.json)","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}