CVE-2023-20233
A vulnerability in the Connectivity Fault Management (CFM) feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to incorrect processing of invalid continuity check messages (CCMs). An attacker could exploit this vulnerability by sending crafted CCMs to an affected device. A successful exploit could allow the attacker to cause the CFM service to crash when a user displays information about maintenance end points (MEPs) for peer MEPs on an affected device.
Key facts
- CVSS score
- 4.3 (v3.1)
- Severity
- MEDIUM
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L- Weakness (CWE)
- CWE-476
- EPSS score
- 0.3% (26th percentile)
- In CISA KEV
- No
- In EU EUVD
- Yes (EUVD-2023-24412)
- Published
- September 13, 2023
- NVD last modified
- June 17, 2026
- Status
- Modified
EU Vulnerability Database (EUVD)
This vulnerability is also tracked by ENISA as EUVD-2023-24412 in the EU Vulnerability Database. Last updated in EUVD on August 2, 2024.
View on the EU Vulnerability DatabaseAffected products
- cisco / ios xr
- cisco / ios xr
Certified products that may be affected
1 FIPS 140 or Common Criteria certified product, from automated matching by sec-certs.org.
- Cisco Network Convergence System 540, 5500 and 5700 (NCS540, NCS5500, NCS5700) Series running IOS-XR, version 7.4.1 - Cisco Systems, Inc. - Common Criteria NSCIB-CC-23-0597525-CR - active
References
Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS
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