CVE-2023-29383

I

n Shadow 4.13, it is possible to inject control characters into fields provided to the SUID program chfn (change finger). Although it is not possible to exploit this directly (e.g., adding a new user fails because \n is in the block list), it is possible to misrepresent the /etc/passwd file when viewed. Use of \r manipulations and Unicode characters to work around blocking of the : character make it possible to give the impression that a new user has been added. In other words, an adversary may be able to convince a system administrator to take the system offline (an indirect, social-engineered denial of service) by demonstrating that "cat /etc/passwd" shows a rogue user account.

Configurations

Configuration 1 (hide)

cpe:2.3:a:shadow_project:shadow:4.13:*:*:*:*:*:*:*

History

03 Nov 2025, 20:16

Type Values Removed Values Added
References
  • () https://lists.debian.org/debian-lts-announce/2025/04/msg00026.html -

06 Feb 2025, 22:15

Type Values Removed Values Added
CWE CWE-125

21 Nov 2024, 07:56

Type Values Removed Values Added
References () https://github.com/shadow-maint/shadow/commit/e5905c4b84d4fb90aefcd96ee618411ebfac663d - Patch () https://github.com/shadow-maint/shadow/commit/e5905c4b84d4fb90aefcd96ee618411ebfac663d - Patch
References () https://github.com/shadow-maint/shadow/pull/687 - Issue Tracking () https://github.com/shadow-maint/shadow/pull/687 - Issue Tracking
References () https://www.trustwave.com/en-us/resources/blogs/spiderlabs-blog/cve-2023-29383-abusing-linux-chfn-to-misrepresent-etc-passwd/ - Exploit, Third Party Advisory () https://www.trustwave.com/en-us/resources/blogs/spiderlabs-blog/cve-2023-29383-abusing-linux-chfn-to-misrepresent-etc-passwd/ - Exploit, Third Party Advisory
References () https://www.trustwave.com/en-us/resources/security-resources/security-advisories/?fid=31797 - Exploit, Third Party Advisory () https://www.trustwave.com/en-us/resources/security-resources/security-advisories/?fid=31797 - Exploit, Third Party Advisory

Information

Published : 2023-04-14 22:15

Updated : 2025-11-03 20:16


NVD link : CVE-2023-29383

Mitre link : CVE-2023-29383

CVE.ORG link : CVE-2023-29383


JSON object : View

Products Affected
CWE
CWE-74

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

CWE-125

Out-of-bounds Read