#VU52860 Input validation error in Exim - CVE-2020-28015

Vulnerability identifier: #VU52860

Vulnerability risk: Low

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

CVE-ID: CVE-2020-28015

CWE-ID: CWE-20

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Exim
Server applications / Mail servers

Vendor: Exim

Description

The vulnerability allows a local user to bypass implemented security restrictions

The vulnerability exists due to insufficient validation of user-supplied input when processing new line characters. A local user can inject a new line character into spool header file and execute arbitrary commands.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Exim: 4.00 - 4.94.1

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External links
https://seclists.org/oss-sec/2021/q2/91

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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.