CVE-2021-21703highCWE-284CWE-787

CVE-2021-21703: fallo de gravedad alta en PHP

PHP-FPM memory access in root process leading to privilege escalation

Publicada el · Actualizada el

Seguir esta CVE+ Monitorear PHP+ Monitorear php7

Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.

21Vexday Risk Score

Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.

ssvc Trackcvss 7.8epss 1.4%
In PHP versions 7.3.x up to and including 7.3.31, 7.4.x below 7.4.25 and 8.0.x below 8.0.12, when running PHP FPM SAPI with main FPM daemon process running as root and child worker processes running as lower-privileged users, it is possible for the child processes to access memory shared with the main process and write to it, modifying it in a way that would cause the root process to conduct invalid memory reads and writes, which can be used to escalate privileges from local unprivileged user to the root user.
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
Productos afectados
PHP Group · PHP
CVEs relacionadas — PHP

En el mismo producto, de las más peligrosas a las menos.

CVE-2026-109619CRITICALRCE via stale global stateEPSS 100.0%KEVCVE-2026-109618CRITICALRCE via OOM corruptionEPSS 100.0%KEVCVE-2024-4577CRITICALArgument Injection in PHP-CGIEPSS 100.0%KEVCVE-2022-31626HIGHmysqlnd/pdo password buffer overflowEPSS 58.1%CVE-2022-31629MEDIUM$_COOKIE names string replacement (. -> _): cookie integrity vulnerabilitiesEPSS 49.6%CVE-2024-2756MEDIUM__Host-/__Secure- cookie bypass due to partial CVE-2022-31629 fixEPSS 38.1%