CVE-2023-20191 Details
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 .
View at NVD
Exploit prediction scoring system (EPSS) score for CVE-2023-20191
EPSS (Exploit Prediction Scoring System): EPSS predicts the likelihood that a vulnerability will be exploited in the wild. A higher percentage means a greater chance of an exploit occurring. The EPSS model produces a probability score between 0 and 1 (0 and 100%).
0.04 Probability of exploitation activity being observed over the next 30 days (13th percentile)
CVSS score for CVE-2023-20191
CVSS (Common Vulnerability Scoring System): An open framework owned and managed by FIRST.Org, Inc. that assigns a numerical score from 0 to 10 to software vulnerabilities to indicate their severity.
5.8 Medium
Products affected by CVE-2023-20191
IOS XR 5.2.4
IOS XR 5.3.2
IOS XR 6.0.2
IOS XR 6.1.4
IOS XR 6.2.25
DVE Score by Bitsight AI
DVE scores complement traditional static scoring systems like CVSS with Bitsight AI powered real-time threat intelligence and underground cyber criminal activity so that security teams can reduce alert fatigue and focus on vulnerabilities most likely to be exploited.
Not available
More on DVE scores

CVE-2023-20191 Global Footprint

Top 10 Identified Countries

Country Observations Percentage
ZW 179 42.32%
RU 39 9.22%
ZA 31 7.33%
CI 19 4.49%
US 18 4.26%
KN 16 3.78%
BD 15 3.55%
HU 15 3.55%
KZ 11 2.60%
VN 10 2.36%

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CVE-2023-20191 Industry Footprint

Top 10 Identified Industries

*Service provider organizations (typically Technology and Telecommunications) are disproportionally represented in the results given their upstream ownership of end-user infrastructure. See our FAQs.

Industry* Observations Percentage
Telecommunications 62 72.94%
Government/Politics 12 14.12%
Technology 9 10.59%
Utilities 1 1.18%
Manufacturing 1 1.18%

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