{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-56020","assignerOrgId":"9119a7d8-5eab-497f-8521-727c672e3725","state":"PUBLISHED","assignerShortName":"cisa-cg","dateReserved":"2026-06-18T14:15:27.103Z","datePublished":"2026-06-18T16:12:05.368Z","dateUpdated":"2026-06-22T12:33:00.797Z"},"containers":{"cna":{"descriptions":[{"lang":"en","value":"The Webmin HTTP server (miniserv.pl) allows unauthenticated attackers to impersonate any user with a configured SSL client certificate by sending a forged HTTP header. A remote attacker can spoof certificate DNs and authenticate as any user. Fixed in 2.641."}],"affected":[{"vendor":"Webmin","product":"Webmin","defaultStatus":"unknown","versions":[{"version":"0","status":"affected","lessThan":"2.641","versionType":"custom"},{"version":"2.641","status":"unaffected"}]}],"problemTypes":[{"descriptions":[{"description":"CWE-290 Authentication Bypass by Spoofing","lang":"en","type":"CWE","cweId":"CWE-290"}]}],"metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":8.1,"attackVector":"NETWORK","baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","integrityImpact":"HIGH","userInteraction":"NONE","attackComplexity":"HIGH","availabilityImpact":"HIGH","privilegesRequired":"NONE","confidentialityImpact":"HIGH"}},{"cvssV4_0":{"version":"4.0","baseScore":9.2,"attackVector":"NETWORK","baseSeverity":"CRITICAL","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","userInteraction":"NONE","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"NONE","subIntegrityImpact":"NONE","vulnIntegrityImpact":"HIGH","subAvailabilityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","vulnConfidentialityImpact":"HIGH"}},{"other":{"type":"ssvc","content":{"timestamp":"2026-05-29T20:04:47.266910Z","id":"CVE-2026-56020","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"Webmin HTTP header authentication bypass","references":[{"name":"url","url":"https://github.com/webmin/webmin/releases/tag/2.641","tags":["release-notes"]},{"name":"url","url":"https://webmin.com/security/#webmin-prior-to-2641","tags":["release-notes"]},{"name":"url","url":"https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/IT/white/2026/va-26-169-02.json"},{"name":"url","url":"https://www.cve.org/CVERecord?id=CVE-2026-56020","tags":["vdb-entry"]}],"credits":[{"value":"Adem El Adeb, vulone.com/vul1.com","lang":"en"}],"datePublic":"2026-06-18T00:00:00.000Z","providerMetadata":{"orgId":"9119a7d8-5eab-497f-8521-727c672e3725","shortName":"cisa-cg","dateUpdated":"2026-06-18T16:12:05.368Z"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-19T03:55:50.732526Z","id":"CVE-2026-56020","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-06-22T12:33:00.797Z"}}]}}