#VU29532 NULL pointer dereference in ZNC - CVE-2020-13775

Vulnerability identifier: #VU29532

Vulnerability risk: Low

CVSSv4.0: 2.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-13775

CWE-ID: CWE-476

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
ZNC
Server applications / IDS/IPS systems, Firewalls and proxy servers

Vendor: ZNC

Description

The vulnerability allows a remote user to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error. A remote authenticated user can pass specially crafted data to the application and perform a denial of service (DoS) attack.

Successful exploitation of the vulnerability requires that the echo-message is not enabled and there is no network.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

ZNC: 1.8.0

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External links
https://github.com/znc/znc/commit/2390ad111bde16a78c98ac44572090b33c3bd2d8
https://github.com/znc/znc/commit/d229761821da38d984a9e4098ad96842490dc001
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/DNVBE4T2DRJRQHFRMHYBTN4OSOL6DBHR/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/HS3DWGXLVRROQQA57UIPMDM6XMVEMBRA/

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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.