CVE-2021-21703
Published: August 31, 2023Last modified: August 31, 2023
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.
Severity score breakdown
Parameter | Value |
---|---|
Base score | 7 |
Attack Vector | LOCAL |
Attack complexity | HIGH |
Privileges required | LOW |
User interaction | NONE |
Scope | UNCHANGED |
Confidentiality | HIGH |
Integrity impact | HIGH |
Availability impact | HIGH |
Vector | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H |
Status
Product | Release | Package | Status |
---|---|---|---|
Alpaquita Linux | 23 LTS | php81 | Not affected (8.1.22-r0) |
Stream | php81 | Not affected (8.1.22-r0) |
References
- 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://lists.fedoraproject.org/archives/list/[email protected]/message/6PZVLICZUJMXOGWOUWSBAEGIVTF6Y6V3/
- https://lists.fedoraproject.org/archives/list/[email protected]/message/JO5RA6YOBGGGKLIA6F6BQRZDDECF5L3R/
- https://lists.fedoraproject.org/archives/list/[email protected]/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