7.8
High
CVE-2021-21703 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…
Description
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.
Affected products and versions
References
- bugs.php.net bugs.php.net
- DSA-4992 www.debian.org
- DSA-4993 www.debian.org
- [oss-security] 20211026 CVE-2021-21703: PHP-FPM 5.3.7 <= 8.0.12 Local Root www.openwall.com
- [debian-lts-announce] 20211027 [SECURITY] [DLA 2794-1] php7.0 security update lists.debian.org
- FEDORA-2021-9f68f5f752 lists.fedoraproject.org
- FEDORA-2021-4140b54de2 lists.fedoraproject.org
- FEDORA-2021-02d218c3be lists.fedoraproject.org
- www.oracle.com www.oracle.com
- security.netapp.com security.netapp.com
- www.oracle.com www.oracle.com
- GLSA-202209-20 security.gentoo.org
Timeline
- Published
- Last modified
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