CVE-2026-6104 (GCVE-0-2026-6104)
Vulnerability from cvelistv5
Published
2026-05-10 04:35
Modified
2026-05-11 13:04
Severity ?
6.3 (Medium) - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:L/SI:N/SA:L/RE:M/U:Amber
CWE
Summary
In PHP versions 8.4.* before 8.4.21 and 8.5.* before 8.5.6, when an encoding name containing an embedded NUL byte is passed to mb_convert_encoding() or related mbstring functions, the code incorrectly assumes that when strncasecmp() returns 0 it means the strings have the same length. This can lead to out-of-bounds read of global memory, potentially causing a crash or information disclosure or crash. Affected functions include mb_convert_encoding(), mb_detect_encoding(), mb_convert_variables(), and mb_detect_order(), as well as the mbstring.detect_order and mbstring.http_output INI settings.
References
Impacted products
Vendor Product Version
PHP Group PHP Version: 8.4.*   ≤
Version: 8.5.*   ≤
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