CVE-2026-6104
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.
CVSS
- Versión: 4.0
- Vector: 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:M/U:Amber
- Puntuación base: 6.3
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.60%
- Percentil entre todas las CVEs puntuadas: 47
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
CWE
- CWE-125
- CWE-125
Referencias
JSON original (NVD)
Mostrar
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"value": "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."
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"value": "En versiones de PHP 8.4.* anteriores a 8.4.21 y 8.5.* anteriores a 8.5.6, cuando un nombre de codificación que contiene un byte NUL incrustado se pasa a mb_convert_encoding() o funciones mbstring relacionadas, el código asume incorrectamente que cuando strncasecmp() devuelve 0 significa que las cadenas tienen la misma longitud. Esto puede llevar a una lectura fuera de límites de la memoria global, lo que podría causar un fallo o revelación de información o un fallo. Las funciones afectadas incluyen mb_convert_encoding(), mb_detect_encoding(), mb_convert_variables() y mb_detect_order(), así como las configuraciones INI mbstring.detect_order y mbstring.http_output."
}
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"lastModified": "2026-07-24T08:10:00.150",
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