CVE-2021-21703

Published Oct 25, 2021

Last updated a year ago

Overview

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.
Source
security@php.net
NVD status
Modified

Risk scores

CVSS 3.1

Type
Primary
Base score
7
Impact score
5.9
Exploitability score
1
Vector string
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

CVSS 2.0

Type
Primary
Base score
6.9
Impact score
10
Exploitability score
3.4
Vector string
AV:L/AC:M/Au:N/C:C/I:C/A:C

Weaknesses

nvd@nist.gov
CWE-787
security@php.net
CWE-284

Social media

Hype score
Not currently trending

Configurations