CVE-2021-21703
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CVSS Score
V3.1EPSS Score
v2025.03.14There is a 0.1% chance that this vulnerability will be exploited in the wild within the next 30 days.
Attack Vector Metrics
Impact Metrics
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.
Available Exploits
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GitHub Security Advisories
Community-driven vulnerability intelligence from GitHub
Advisory Details
CVSS Scoring
CVSS Score
CVSS Vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
References
Advisory provided by GitHub Security Advisory Database. Published: May 24, 2022, Modified: May 24, 2022