#VU67972 Memory leak in LibVNCServer - CVE-2020-29260

Vulnerability identifier: #VU67972

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-29260

CWE-ID: CWE-401

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
LibVNCServer
Server applications / Remote management servers, RDP, SSH

Vendor: LibVNC

Description
The vulnerability allows a remote attacker to perform DoS attack on the target system.

The vulnerability exists due memory leak within the rfbClientCleanup() function. A remote attacker can force the server to leak memory and perform denial of service attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

LibVNCServer: 0.9.0 - 0.9.13

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External links
https://github.com/LibVNC/libvncserver/commit/bef41f6ec4097a8ee094f90a1b34a708fbd757ec
https://lists.debian.org/debian-lts-announce/2022/09/msg00035.html

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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