CVE-2026-91767 (GCVE-0-2026-91767)

Vulnerability from cvelistv5 – Published: 2026-09-25 20:53 – Updated: 2026-09-28 13:31
VLAI
Title
Heap-buffer-overflow in php_openssl_matches_wildcard_name on crafted server cert wildcard CN
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.
Severity
6.5 (Medium)
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-28 12:56 UTC
CWE
  • CWE-122 - Heap-based buffer overflow
Assigner
References
Impacted products
Vendor Product Version
PHP Group PHP Affected: 8.2.* , < 8.2.34 (semver)
Affected: 8.3.* , < 8.3.35 (semver)
Affected: 8.4.* , < 8.4.26 (semver)
Affected: 8.5.* , < 8.5.11 (semver)
Create a notification for this product.
Date Public
2026-09-25 20:49
Credits
Mohamed Sayed (flex0geek) Jakub Zelenka Arnaud Le Blanc
Show details on NVD website
To clipboard 

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