Privilege escalation in Sympa

1) OS Command Injection

EUVDB-ID: #VU47651

Risk: Low

CVSSv3.1: 7.7 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-26880

CWE-ID: CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

Exploit availability: No

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to incorrect default permissions for the sympa.conf configuration file. A local user with access to modify the file (e.g. the sympa user account) can injection and execute arbitrary OS commands in the system with root privileges via the setuid sympa_newaliases-wrapper executable by parsing the modified sympa.conf file.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Sympa: 0.001 - 6.2b.9

External links

http://github.com/sympa-community/sympa/issues/1009
http://github.com/sympa-community/sympa/issues/943#issuecomment-704779420
http://github.com/sympa-community/sympa/issues/943#issuecomment-704842235

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.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

The attacker would have to login to the system and perform certain actions in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

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