CVE-2021-21703
Estado: ModificadaAlta (7)—
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
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 7
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.43%
- Percentil entre todas las CVEs puntuadas: 72
- 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 (5)
CWE
- CWE-284, CWE-787
- CWE-787
Referencias
- http://www.openwall.com/lists/oss-security/2021/10/26/7
- https://bugs.php.net/bug.php?id=81026
- https://lists.debian.org/debian-lts-announce/2021/10/msg00021.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6PZVLICZUJMXOGWOUWSBAEGIVTF6Y6V3/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JO5RA6YOBGGGKLIA6F6BQRZDDECF5L3R/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PBM3KKB3RY2YPOKNMC4HIH7IH3T3WC74/
- https://security.gentoo.org/glsa/202209-20
- https://security.netapp.com/advisory/ntap-20211118-0003/
- https://www.debian.org/security/2021/dsa-4992
- https://www.debian.org/security/2021/dsa-4993
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://www.oracle.com/security-alerts/cpujan2022.html
- http://www.openwall.com/lists/oss-security/2021/10/26/7
- https://bugs.php.net/bug.php?id=81026
- https://lists.debian.org/debian-lts-announce/2021/10/msg00021.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6PZVLICZUJMXOGWOUWSBAEGIVTF6Y6V3/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JO5RA6YOBGGGKLIA6F6BQRZDDECF5L3R/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PBM3KKB3RY2YPOKNMC4HIH7IH3T3WC74/
- https://security.gentoo.org/glsa/202209-20
- https://security.netapp.com/advisory/ntap-20211118-0003/
- https://www.debian.org/security/2021/dsa-4992
- https://www.debian.org/security/2021/dsa-4993
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://www.oracle.com/security-alerts/cpujan2022.html
JSON original (NVD)
Mostrar
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