CVE-2026-91767
PHP Group PHP
Published 25 Sept 2026 · updated 29 Sept 2026 · Awaiting Analysis
6.5 Medium · CVSS 3.1, php.net
Description
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 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.