CVE-2026-91767

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/php/php-src/security/advisories/GHSA-xr7j-rvgx-xq5p

Configurations

No configuration.

History

25 Sep 2026, 21:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-25 21:17

Updated : 2026-09-29 21:27

NVD link : CVE-2026-91767

Mitre link : CVE-2026-91767

CVE.ORG link : CVE-2026-91767

JSON object : View

Products Affected

No product.

CWE

CWE-122

Heap-based Buffer Overflow

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