Privilege escalation in Net-snmp

1) UNIX symbolic link following

EUVDB-ID: #VU45744

Risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-15861

CWE-ID: CWE-61 - UNIX Symbolic Link (Symlink) Following

Exploit availability: No

Description

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

The vulnerability exists due to a symlink following issue in snmpd. A local user can bypass implemented security mechanism via *snmp-mibs-downloader package* and execute arbitrary commands on the system as root.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Net-snmp: 5.0 - 5.8.pre3

CPE2.3

• cpe:2.3:a:net-snmp_sourceforge_net:net-snmp:5.0:*:*:*:*:*:*:*
• cpe:2.3:a:net-snmp_sourceforge_net:net-snmp:5.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:net-snmp_sourceforge_net:net-snmp:5.0.2:*:*:*:*:*:*:*

External links

https://github.com/net-snmp/net-snmp/commit/4fd9a450444a434a993bc72f7c3486ccce41f602
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=966599

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.