In PHP versions 7.2.x below 7.2.29, 7.3.x below 7.3.16 and 7.4.x below 7.4.4, while using get_headers() with user-supplied URL, if the URL contains zero (\0) character, the URL will be silently truncated at it. This may cause some software to make incorrect assumptions about the target of the get_headers() and possibly send some information to a wrong server.
https://bugs.php.net/bug.php?id=79329
https://security.netapp.com/advisory/ntap-20200403-0001/
https://lists.debian.org/debian-lts-announce/2020/04/msg00021.html
https://usn.ubuntu.com/4330-2/
http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00025.html
https://www.debian.org/security/2020/dsa-4717
Source: MITRE
Published: 2020-04-01
Updated: 2022-05-08
Type: NVD-CWE-Other
Base Score: 4.3
Vector: AV:N/AC:M/Au:N/C:P/I:N/A:N
Impact Score: 2.9
Exploitability Score: 8.6
Severity: MEDIUM
Base Score: 4.3
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
Impact Score: 1.4
Exploitability Score: 2.8
Severity: MEDIUM