CVE-2026-91767 (GCVE-0-2026-91767)
Vulnerability from cvelistv5
Published
2026-09-25 20:53
Modified
2026-09-28 13:31
Severity ?
6.5 (Medium) - CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CWE
  • CWE-122 - Heap-based buffer overflow
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 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.
References
Impacted products
Vendor Product Version
PHP Group PHP Version: 8.2.*   ≤
Version: 8.3.*   ≤
Version: 8.4.*   ≤
Version: 8.5.*   ≤
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