CVE-2026-91767
Heap-buffer-overflow in php_openssl_matches_wildcard_name on crafted server cert wildcard CN
CVSS Score
6.5
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-122 |
| Vendor | php group |
| Product | php |
| Published | Sep 25, 2026 |
Stay Ahead of the Next One
Get instant alerts for php group php
Be the first to know when new medium vulnerabilities affecting php group php are published — delivered to Slack, Telegram or Discord.
Get Free Alerts →
Free · No credit card · 60 sec setup
CVSS v3 Breakdown
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Attack Vector
Adjacent
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None
Affected Versions
PHP Group / PHP
8.2.* < 8.2.34 8.3.* < 8.3.35 8.4.* < 8.4.26 8.5.* < 8.5.11
References
Credits
🔍 Mohamed Sayed (flex0geek) Jakub Zelenka Arnaud Le Blanc