{"cve":{"cve_id":"CVE-2026-67278","is_kev":false,"kev_date_added":null,"kev_vendor_project":null,"kev_product":null,"kev_vulnerability_name":null,"kev_short_description":null,"kev_required_action":null,"kev_due_date":null,"kev_known_ransomware":null,"kev_notes":null,"kev_cwes":null,"epss_score":0.00155,"epss_percentile":0.04962,"epss_as_of":"2026-09-15","description":"MikroTik RouterOS accepts malformed RSA/PKCS#1 v1.5 signatures across RSA-based services, including TLS/X.509 certificate validation and SSH host-key authentication. Because its trust store includes an e=3 root CA, an attacker controlling or redirecting an outbound RouterOS TLS connection can use the root’s public certificate - without its private key - to forge a trusted intermediate and issue certificates for arbitrary hostnames, enabling TLS server impersonation. The same permissive verification also undermines RSA-based SSH authentication.\n\n\n\nThis issue affects only 7.x branch was fixed in versions: 7.23.6 (Long-term) and 7.24.3 (Stable).\nReleases 7.23.4 and 7.24.2 included an incomplete fix.","published_at":"2026-09-05T20:00:57.258000Z","last_modified_at":"2026-09-17T15:16:50.947000Z","cvss_v3_score":null,"cvss_v3_vector":null,"cvss_v3_severity":null,"cvss_v4_score":6.3,"cvss_v4_vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","cvss_v4_severity":"MEDIUM","ssvc_decision":null,"ssvc_exploitation":null,"ssvc_automatable":null,"ssvc_technical_impact":null,"cwes":["CWE-347"],"nvd_references":["https://cert.pl/en/posts/2026/09/mikrotik-routeros-cve","https://cert.pl/en/posts/2026/09/vulnerabilities-in-mikrotik-routeros-actively-exploited/","https://npratley.net/reversing-mikrotiks-silent-patch-the-routeros-7-23-4-fix-they-wouldnt-explain/","https://mikrotik.com/supportsec/september-2026-vulnerability/","https://forum.mikrotik.com/t/7-23-6-long-term-is-released/273139","https://forum.mikrotik.com/t/7-24-3-stable-is-released/273138"],"vuln_status":"Awaiting Analysis","trending_score":null,"is_trending":false,"has_trended":false,"trended_number_one":false,"trending_peak_score":null,"trending_peak_rank":null,"started_trending_at":null,"trended_number_one_at":null,"summary_generated":null,"summary_generated_at":null,"summary_model":null,"created_at":"2026-09-05T22:34:30.385310Z","updated_at":"2026-09-18T12:24:03.503015Z"},"effective_severity":"MEDIUM","badges":[],"impact_analysis":[],"cvss_v3_decoded":{"version":null,"metrics":[]},"cvss_v4_decoded":{"version":"4.0","metrics":[{"metric":"AV","name":"Attack Vector","value":"N","value_label":"Network"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"AT","name":"Attack Requirements","value":"P","value_label":"Present"},{"metric":"PR","name":"Privileges Required","value":"N","value_label":"None"},{"metric":"UI","name":"User Interaction","value":"N","value_label":"None"},{"metric":"VC","name":"Confidentiality (Vulnerable System)","value":"L","value_label":"Low"},{"metric":"VI","name":"Integrity (Vulnerable System)","value":"L","value_label":"Low"},{"metric":"VA","name":"Availability (Vulnerable System)","value":"N","value_label":"None"},{"metric":"SC","name":"Confidentiality (Subsequent System)","value":"N","value_label":"None"},{"metric":"SI","name":"Integrity (Subsequent System)","value":"N","value_label":"None"},{"metric":"SA","name":"Availability (Subsequent System)","value":"N","value_label":"None"}]},"affected":[{"vendor_slug":"mikrotik","vendor_name":"MikroTik","product_slug":"routeros","product_name":"RouterOS","version_start":"7.24","version_start_inclusive":true,"version_end":"7.24.2","version_end_inclusive":false,"cpe23_uri":"cve5:mikrotik:routeros:7.24:7.24.2"},{"vendor_slug":"mikrotik","vendor_name":"MikroTik","product_slug":"routeros","product_name":"RouterOS","version_start":"7.0.0","version_start_inclusive":true,"version_end":"7.23.4","version_end_inclusive":false,"cpe23_uri":"cve5:mikrotik:routeros:7.0.0:7.23.4"},{"vendor_slug":"mikrotik","vendor_name":"MikroTik","product_slug":"routeros","product_name":"RouterOS","version_start":"6.0.0","version_start_inclusive":true,"version_end":"6.49.21","version_end_inclusive":false,"cpe23_uri":"cve5:mikrotik:routeros:6.0.0:6.49.21"},{"vendor_slug":"mikrotik","vendor_name":"MikroTik","product_slug":"routeros","product_name":"RouterOS","version_start":"7.24","version_start_inclusive":true,"version_end":"7.24.3","version_end_inclusive":false,"cpe23_uri":"cve5:mikrotik:routeros:7.24:7.24.3"},{"vendor_slug":"mikrotik","vendor_name":"MikroTik","product_slug":"routeros","product_name":"RouterOS","version_start":"7.0.0","version_start_inclusive":true,"version_end":"7.23.6","version_end_inclusive":false,"cpe23_uri":"cve5:mikrotik:routeros:7.0.0:7.23.6"}],"exploit_refs":[],"news":[],"references":[{"url":"https://cert.pl/en/posts/2026/09/mikrotik-routeros-cve","source_type":"MISC","tags":[]},{"url":"https://cert.pl/en/posts/2026/09/vulnerabilities-in-mikrotik-routeros-actively-exploited/","source_type":"MISC","tags":[]},{"url":"https://npratley.net/reversing-mikrotiks-silent-patch-the-routeros-7-23-4-fix-they-wouldnt-explain/","source_type":"MISC","tags":["patch"]},{"url":"https://mikrotik.com/supportsec/september-2026-vulnerability/","source_type":"MISC","tags":[]},{"url":"https://forum.mikrotik.com/t/7-23-6-long-term-is-released/273139","source_type":"MISC","tags":[]},{"url":"https://forum.mikrotik.com/t/7-24-3-stable-is-released/273138","source_type":"MISC","tags":[]}],"timeline":[{"type":"published","at":"2026-09-05T20:00:57.258000Z","label":"CVE published","source":null}]}