{"id":"CVE-2026-67277","state":"PUBLISHED","title":"Kernel memory disclosure and denial of service in MikroTik RouterOS btest service","description":"RouterOS accepts a \"related\" btest connection before the corresponding primary session has completed authentication. An unauthenticated client can use this state to start an IPv4 UDP test. With \"random-data=false\", the sender transmits an uninitialized tail from a kernel packet buffer. A separate unchecked, inverted packet-size interval causes unsigned integer underflow, anomalously large fragmented output, and can restart the RouterOS kernel.\n\n\n\nThis issue was fixed in versions: 6.49.21 (Long-term), 7.23.4 (Long-term) and 7.24.2 (Stable)","publishedAt":"2026-09-05T20:00:56.614Z","updatedAt":"2026-09-11T03:55:58.675Z","severity":{"score":8.8,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N","source":"CERT-PL"},"assigner":"CERT-PL","products":["Mikrotik RouterOS"],"affected":[{"vendor":"Mikrotik","product":"RouterOS","defaultStatus":"unaffected","versions":[{"version":"7.24","status":"affected","lessThan":"7.24.2","versionType":"custom"},{"version":"7.0.0","status":"affected","lessThan":"7.23.4","versionType":"custom"},{"version":"6.0.0","status":"affected","lessThan":"6.49.21","versionType":"custom"}]}],"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/6-49-21-long-term-is-released/272802","https://forum.mikrotik.com/t/7-23-4-long-term-is-released/272801","https://forum.mikrotik.com/t/7-24-2-stable-is-released/272800","https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-67277"],"weaknesses":["CWE-306"],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/67xxx/CVE-2026-67277.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-67277","state":"PUBLISHED","datePublished":"2026-09-05T20:00:56.614Z","dateUpdated":"2026-09-11T03:55:58.675Z","assignerShortName":"CERT-PL","assignerOrgId":"4bb8329e-dd38-46c1-aafb-9bf32bcb93c6","dateReserved":"2026-07-29T11:59:30.538Z"},"containers":{"cna":{"title":"Kernel memory disclosure and denial of service in MikroTik RouterOS btest service","descriptions":[{"lang":"en","value":"RouterOS accepts a \"related\" btest connection before the corresponding primary session has completed authentication. An unauthenticated client can use this state to start an IPv4 UDP test. With \"random-data=false\", the sender transmits an uninitialized tail from a kernel packet buffer. A separate unchecked, inverted packet-size interval causes unsigned integer underflow, anomalously large fragmented output, and can restart the RouterOS kernel.\n\n\n\nThis issue was fixed in versions: 6.49.21 (Long-term), 7.23.4 (Long-term) and 7.24.2 (Stable)"}],"affected":[{"vendor":"Mikrotik","product":"RouterOS","defaultStatus":"unaffected","versions":[{"version":"7.24","status":"affected","lessThan":"7.24.2","versionType":"custom"},{"version":"7.0.0","status":"affected","lessThan":"7.23.4","versionType":"custom"},{"version":"6.0.0","status":"affected","lessThan":"6.49.21","versionType":"custom"}]}],"references":[{"url":"https://cert.pl/en/posts/2026/09/mikrotik-routeros-cve","tags":["third-party-advisory"]},{"url":"https://cert.pl/en/posts/2026/09/vulnerabilities-in-mikrotik-routeros-actively-exploited/","tags":["technical-description"]},{"url":"https://npratley.net/reversing-mikrotiks-silent-patch-the-routeros-7-23-4-fix-they-wouldnt-explain/","tags":["exploit"]},{"url":"https://mikrotik.com/supportsec/september-2026-vulnerability/","tags":["vendor-advisory"]},{"url":"https://forum.mikrotik.com/t/6-49-21-long-term-is-released/272802","tags":["release-notes"]},{"url":"https://forum.mikrotik.com/t/7-23-4-long-term-is-released/272801","tags":["release-notes"]},{"url":"https://forum.mikrotik.com/t/7-24-2-stable-is-released/272800","tags":["release-notes"]}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"LOW","subConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","subIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED","version":"4.0","baseSeverity":"HIGH","baseScore":8.8,"vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-306","lang":"en","description":"CWE-306 Missing authentication for critical function","type":"CWE"}]}],"providerMetadata":{"shortName":"CERT-PL","orgId":"4bb8329e-dd38-46c1-aafb-9bf32bcb93c6","dateUpdated":"2026-09-05T20:39:44.166Z"},"cpeApplicability":[{"operator":"OR","nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:mikrotik:routeros:*:*:*:*:*:*:*:*","versionStartIncluding":"0.0.0","versionEndExcluding":"7.25.1"}]}]}],"credits":[{"lang":"en","value":"Sławomir Rozbicki (CERT.PL)","type":"finder"}],"source":{"discovery":"INTERNAL"},"x_generator":{"engine":"Vulnogram 1.0.3"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-67277","tags":["government-resource"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-08T00:00:00+00:00","options":[{"Exploitation":"active"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3","id":"CVE-2026-67277"}}},{"other":{"type":"kev","content":{"dateAdded":"2026-09-10","reference":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-67277"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-11T03:55:58.675Z"},"timeline":[{"time":"2026-09-10T00:00:00.000Z","lang":"en","value":"CVE-2026-67277 added to CISA KEV"}]}]}}}