#VU75589 Improper Neutralization of Special Elements in Output Used by a Downstream Component in shadow - CVE-2023-29383

Vulnerability identifier: #VU75589

Vulnerability risk: Low

CVSSv4.0: 1.1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2023-29383

CWE-ID: CWE-74

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
shadow
Universal components / Libraries / Libraries used by multiple products

Vendor: Mark Florian

Description

The vulnerability allows a local user to inject arbitrary code.

The vulnerability exists due to an input validation error when processing fields provided to the SUID program chfn (change finger). A local user can inject and execute arbitrary code or misrepresent existing files.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

shadow: 4.0.0 - 4.13

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External links
https://github.com/shadow-maint/shadow/commit/e5905c4b84d4fb90aefcd96ee618411ebfac663d
https://www.trustwave.com/en-us/resources/security-resources/security-advisories/?fid=31797
https://github.com/shadow-maint/shadow/pull/687
https://www.trustwave.com/en-us/resources/blogs/spiderlabs-blog/cve-2023-29383-abusing-linux-chfn-to-misrepresent-etc-passwd/

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.