In PHP versions 7.2.x below 7.2.28, 7.3.x below 7.3.15 and 7.4.x below 7.4.3, when using file upload functionality, if upload progress tracking is enabled, but session.upload_progress.cleanup is set to 0 (disabled), and the file upload fails, the upload procedure would try to clean up data that does not exist and encounter null pointer dereference, which would likely lead to a crash.
https://bugs.php.net/bug.php?id=79221
http://lists.opensuse.org/opensuse-security-announce/2020-03/msg00023.html
https://security.gentoo.org/glsa/202003-57
https://lists.debian.org/debian-lts-announce/2020/03/msg00034.html
https://usn.ubuntu.com/4330-1/
https://www.debian.org/security/2020/dsa-4717
Source: MITRE
Published: 2020-02-27
Updated: 2022-01-01
Type: CWE-476
Base Score: 4.3
Vector: AV:N/AC:M/Au:N/C:N/I:N/A:P
Impact Score: 2.9
Exploitability Score: 8.6
Severity: MEDIUM
Base Score: 7.5
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Impact Score: 3.6
Exploitability Score: 3.9
Severity: HIGH