{"id":"CVE-2026-85590","state":"PUBLISHED","title":"phpMyFAQ before 4.1.8 Authentication Bypass via Two-Factor Disable","description":"phpMyFAQ before 4.1.8 contains an authentication bypass vulnerability in its two-factor authentication (TOTP) disable functionality. The removeTwofactorConfig() handler (reachable via POST /api/user/remove-twofactor) verifies only that the user is logged in and that a valid CSRF token is supplied, then disables TOTP without requiring password re-entry or a current TOTP code. The same downgrade is also reachable inline via PUT /api/user/data/update, which accepts a plain twofactor_enabled form field under the same session+CSRF-only guard. An attacker who has hijacked a user's session can silently strip two-factor protection from any account, including administrator accounts, after which password-only authentication succeeds.","publishedAt":"2026-09-04T11:29:56.063Z","updatedAt":"2026-09-04T14:01:35.450Z","severity":{"score":7.1,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N","source":"VulnCheck"},"assigner":"VulnCheck","products":["thorsten phpMyFAQ"],"affected":[{"vendor":"thorsten","product":"phpMyFAQ","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"4.1.8","versionType":"semver"},{"version":"4.1.8","status":"unaffected","versionType":"semver"}]}],"references":["https://github.com/thorsten/phpMyFAQ/security/advisories/GHSA-h96g-59xp-7r5m","https://www.vulncheck.com/advisories/phpmyfaq-before-4.1.8-authentication-bypass-via-two-factor-disable"],"weaknesses":["CWE-308"],"ingestedAt":"2026-10-29T20:13:15.269Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/85xxx/CVE-2026-85590.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-85590","state":"PUBLISHED","datePublished":"2026-09-04T11:29:56.063Z","dateUpdated":"2026-09-04T14:01:35.450Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-09-04T10:59:00.162Z"},"containers":{"cna":{"title":"phpMyFAQ before 4.1.8 Authentication Bypass via Two-Factor Disable","descriptions":[{"lang":"en","value":"phpMyFAQ before 4.1.8 contains an authentication bypass vulnerability in its two-factor authentication (TOTP) disable functionality. The removeTwofactorConfig() handler (reachable via POST /api/user/remove-twofactor) verifies only that the user is logged in and that a valid CSRF token is supplied, then disables TOTP without requiring password re-entry or a current TOTP code. The same downgrade is also reachable inline via PUT /api/user/data/update, which accepts a plain twofactor_enabled form field under the same session+CSRF-only guard. An attacker who has hijacked a user's session can silently strip two-factor protection from any account, including administrator accounts, after which password-only authentication succeeds."}],"affected":[{"vendor":"thorsten","product":"phpMyFAQ","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"4.1.8","versionType":"semver"},{"version":"4.1.8","status":"unaffected","versionType":"semver"}]}],"references":[{"url":"https://github.com/thorsten/phpMyFAQ/security/advisories/GHSA-h96g-59xp-7r5m","tags":["vendor-advisory"],"name":"GitHub Security Advisory (GHSA-h96g-59xp-7r5m)"},{"url":"https://www.vulncheck.com/advisories/phpmyfaq-before-4.1.8-authentication-bypass-via-two-factor-disable","name":"VulnCheck Advisory: phpMyFAQ before 4.1.8 Authentication Bypass via Two-Factor Disable","tags":["third-party-advisory"]}],"metrics":[{"format":"CVSS","cvssV4_0":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N","attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"LOW","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"HIGH","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":7.1,"baseSeverity":"HIGH"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-308","lang":"en","description":"Use of Single-factor Authentication","type":"CWE"}]}],"providerMetadata":{"shortName":"VulnCheck","orgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateUpdated":"2026-09-04T11:29:56.063Z"},"datePublic":"2026-08-20T00:00:00.000Z","cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:phpmyfaq:phpmyfaq:*:*:*:*:*:*:*:*","versionEndExcluding":"4.1.8"}]}]}],"credits":[{"lang":"en","value":"skeletonsec","type":"reporter"}],"x_generator":{"engine":"vulncheck-endgame"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/thorsten/phpMyFAQ/security/advisories/GHSA-h96g-59xp-7r5m","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-04T13:58:27.504529Z","id":"CVE-2026-85590","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-04T14:01:35.450Z"}}]}}}