CVE-2023-20233

mediumpriority · track · 26EPSS 0.003 · 28 %ileDEEURUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.34% (28th) EPSS
CVSS 6.5 · medium
Is it mine?
70 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · scored 2026-10-28

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.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

02

cvss

Technical severity, 0–10. One row per scoring source.

6.5
010

base score 0–10 · higher = more severe · hover a vector to decode

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 3.6
v3.14.3mediumAV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Lsecondary · FSTEC (BDU) RU
v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Lsecondary · ENISA EU
v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Lsecondary · psirt@cisco.com USexploitability 2.8 · impact 1.4
v3.16mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Lsecondary · Cisco PSIRT US
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-354USprimaryCWE-476USCWE-476US
04

affected products (70)

Products and version ranges known to be affected.

showing 20 of 70
05

advisories (2)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2023-2355Cisco IOS XR: Mehrere SchwachstellenDeutsch2023-09-13csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in Cisco IOS XR ausnutzen, um beliebigen Code auszuführen, Sicherheitsmaßnahmen zu umgehen oder einen Denial-of-Service-Zustand zu verursachen.

  • cisco-sa-ios-xr-cfm-3pWN8MKtCisco IOS XR Software Connectivity Fault Management Denial of Service Vulnerability2023-09-13csaf · cisco_csafUS

    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. Cisco has released software updates that address this vulnerability. There are no 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 ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-75241"].

06

also known as (4)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducisco_csafcert_bundNVDCVE.orgMITRE
published 2023-09-13modified 2026-06-17
09

references (5)

External citations — patches, advisories, analysis.

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