{"schema_version":"public-product-v1.1","generated_at":"2026-07-21T11:18:27Z","exposure_verdict":"not_assessed","verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","advisory":{"id":"cisco-sa-ios-xr-cfm-3pWN8MKt","slug":"cisco-sa-ios-xr-cfm-3pwn8mkt","vendor":"Cisco","title":"Cisco IOS XR Software Connectivity Fault Management Denial of Service Vulnerability","summary":"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 available at the following link:https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-xr-cfm-3pWN8MKt 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.","severity":"Medium","published_at":"2023-09-13T16:00:00Z","updated_at":"2023-09-13T16:00:00Z","source_url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-xr-cfm-3pWN8MKt","csaf_url":"https://sec.cloudapps.cisco.com/security/center/contentjson/CiscoSecurityAdvisory/cisco-sa-ios-xr-cfm-3pWN8MKt/csaf/cisco-sa-ios-xr-cfm-3pWN8MKt.json","exposure_verdict":"not_assessed","verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure."},"freshness":{"last_source_refreshed_at":"2026-07-21T05:16:34Z","latest_source_refresh_at":"2026-07-21T05:16:34Z","oldest_source_refresh_at":"2026-07-21T03:00:03Z","all_sources_fresh":true,"sources":[{"source":"cisco_advisories","label":"Cisco advisories","last_success_at":"2026-07-21T03:00:03Z","stale":false},{"source":"cisco_csaf","label":"Cisco CSAF","last_success_at":"2026-07-21T05:14:24Z","stale":false},{"source":"nvd_cves","label":"NVD CVEs","last_success_at":"2026-07-21T05:16:30Z","stale":false},{"source":"cisa_kev","label":"CISA KEV","last_success_at":"2026-07-21T05:16:31Z","stale":false},{"source":"first_epss","label":"EPSS","last_success_at":"2026-07-21T05:16:34Z","stale":false}]},"summary":{"cve_count":1,"visible_product_count":1,"public_evidence_count":1,"kev_count":0,"highest_epss":0.00273},"cves":[{"id":"CVE-2023-20233","kev":false,"epss":{"score":0.00273,"percentile":0.19326,"score_date":"2026-07-20","updated_at":"2026-07-21T05:16:34Z"}}],"public_evidence":[{"product":{"name":"Cisco IOS XR Software","slug":"cisco-ios-xr-software","vendor":"Cisco"},"cve":{"id":"CVE-2023-20233"},"evidence_type":"structured_affected","evidence_label":{"scope":"CSAF product evidence","label":"product_status known affected"},"evidence_source":"Cisco CSAF","source":"Cisco CSAF","source_document_fetched_at":"2026-07-20T03:58:08Z","csaf_status":"known_affected","csaf_product_status":"known_affected","csaf_product_status_path":"vulnerabilities[].product_status.known_affected","raw_product_name":"Cisco IOS XR Software","exposure_verdict":"not_assessed","verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","exposure_verdict_reason":"Public evidence does not evaluate exact release, platform, enabled features, configuration, compensating controls, or live exposure.","kev":false,"epss":{"score":0.00273,"score_date":"2026-07-20","updated_at":"2026-07-21T05:16:34Z"},"published_at":"2023-09-13T16:00:00Z","updated_at":"2023-09-13T16:00:00Z","advisory_updated_at":"2023-09-13T16:00:00Z","source_url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-xr-cfm-3pWN8MKt","remediation":{"url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-xr-cfm-3pWN8MKt"},"row_display_order":1}]}