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

Vulnerability from cvelistv5 – Published: 2026-09-25 20:53 – Updated: 2026-09-25 20:53
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
CWE
  • CWE-122 - Heap-based buffer overflow
Assigner
References
Impacted products
Vendor Product Version CPE status
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)
guessed 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
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              "value": "\u003cp\u003e\u003ccode\u003ephp_openssl_matches_wildcard_name()\u003c/code\u003e in \u003ccode\u003eext/openssl/xp_ssl.c\u003c/code\u003e underflows the length argument passed to \u003ccode\u003ememchr()\u003c/code\u003e 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 \u003ccode\u003eSIZE_MAX\u003c/code\u003e bytes past the end of a heap allocation. The path is reachable from any default client stream, because \u003ccode\u003everify_peer_name\u003c/code\u003e is enabled by default.\u003c/p\u003e"
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    "dateReserved": "2026-09-15T00:41:16.041Z",
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          }
        ],
        "id": "CVE-2026-91767",
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