{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-33543","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-03-20T18:05:11.832Z","datePublished":"2026-06-24T21:01:16.544Z","dateUpdated":"2026-06-25T13:22:14.263Z"},"containers":{"cna":{"title":"FOSSBilling: Authentication bypass allows unauthenticated administrator creation","problemTypes":[{"descriptions":[{"cweId":"CWE-288","lang":"en","description":"CWE-288: Authentication Bypass Using an Alternate Path or Channel","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-306","lang":"en","description":"CWE-306: Missing Authentication for Critical Function","type":"CWE"}]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"HIGH","vulnIntegrityImpact":"HIGH","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":9.3,"baseSeverity":"CRITICAL","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","version":"4.0"}}],"references":[{"name":"https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-28mh-j262-q49w","tags":["x_refsource_CONFIRM"],"url":"https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-28mh-j262-q49w"},{"name":"https://github.com/FOSSBilling/FOSSBilling/releases/tag/0.8.0","tags":["x_refsource_MISC"],"url":"https://github.com/FOSSBilling/FOSSBilling/releases/tag/0.8.0"}],"affected":[{"vendor":"FOSSBilling","product":"FOSSBilling","versions":[{"version":"< 0.8.0","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-06-24T21:01:16.544Z"},"descriptions":[{"lang":"en","value":"FOSSBilling is a free, open-source billing and client management system. Versions 0.7.2 and prior expose a guest API endpoint, /api/guest/staff/create, intended for initial administrator bootstrap. Due to a flawed admin-existence check, the endpoint remains usable after an administrator already exists. The flawed guard check uses is_countable() on a value that returns a Model_Admin object or null rather than a countable type, causing the expression to always evaluate as true and bypass the intended protection. As a result, an attacker can reach the unprotected endpoint to create a new administrator account and immediately authenticate, gaining a fully privileged admin session even when an admin already exists. This issue has been fixed in version 0.8.0."}],"source":{"advisory":"GHSA-28mh-j262-q49w","discovery":"UNKNOWN"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-25T13:22:04.810298Z","id":"CVE-2026-33543","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"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":"2026-06-25T13:22:14.263Z"}}]}}