CVE-2023-20191 Auth bypass in Cisco IOS XR Software

Medium 5.8 Published 13 Sep 2023 Updated 2 Aug 2024

Unauthenticated remote attackers can bypass configured Access Control Lists on MPLS interfaces in Cisco IOS XR Software.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2023-20191?

CVE-2023-20191 is a medium-severity authentication bypass vulnerability in Cisco Ios Xr, published on 13 Sep 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A vulnerability in the access control list (ACL) processing on MPLS interfaces in the ingress direction of Cisco IOS XR Software could allow an unauthenticated, remote attacker to bypass a configured ACL. This vulnerability is due to incomplete support for this feature. An attacker could exploit this vulnerability by attempting to send traffic through an affected device. A successful exploit could allow the attacker to bypass an ACL on the affected device. There are workarounds that address this vulnerability. This advisory is part of the September 2023 release of the Cisco IOS XR Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see Cisco Event Response: September 2023 Semiannual Cisco IOS XR Software Security Advisory Bundled Publication .

Weakness: CWE-863, CWE-284

Which versions are affected by CVE-2023-20191?

It affects 1 product.

Products include Cisco Ios Xr.

How do I fix CVE-2023-20191?

No fix has been published for CVE-2023-20191 yet. Limit exposure of the affected software until one is available.

Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.

Is CVE-2023-20191 being exploited?

There is no known exploitation of CVE-2023-20191 in the wild and no public exploit code.

All Cisco Ios Xr vulnerabilities

Sources

Also known as GHSA-5hxg-4c73-j4wf.