#VU29535 Double Free in Net-snmp - CVE-2019-20892

Vulnerability identifier: #VU29535

Vulnerability risk: Medium

CVSSv4.0: 6.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2019-20892

CWE-ID: CWE-415

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Net-snmp
Server applications / Remote management servers, RDP, SSH

Vendor: net-snmp.sourceforge.net

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error when processing an SNMPv3 GetBulk request in usm_free_usmStateReference in snmplib/snmpusm.c in net-snmp. A remote attacker can pass specially crafted data to the application, trigger double free error and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Net-snmp: 3.0 - 5.8.pre3

---

External links
https://www.openwall.com/lists/oss-security/2020/06/25/4
https://bugs.launchpad.net/ubuntu/+source/net-snmp/+bug/1877027
https://bugzilla.redhat.com/show_bug.cgi?id=1663027
https://github.com/net-snmp/net-snmp/commit/5f881d3bf24599b90d67a45cae7a3eb099cd71c9
https://sourceforge.net/p/net-snmp/bugs/2923/

---

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

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