{"id":"CVE-2026-63440","published":"2026-11-06T21:17:10.137","lastModified":"2026-11-11T05:19:50.383","description":"2FAuth is a web app to manage Two-Factor Authentication (2FA) accounts and generate their security codes. Prior to 8.0.0, the otpauth image-fetch path validates a hostname through ValidatesUrls::isExternalHost() and then lets IconService::storeRemoteImage() resolve the same hostname again for the HTTP request. When external otpauth image fetching is enabled, an authenticated user controlling low-TTL authoritative DNS can return a public address during validation and an internal address during the later connection, bypassing the private-address deny list to reach loopback, private-network, link-local, or cloud metadata endpoints. This issue is fixed in version 8.0.0.","cvssScore":5.9,"cvssSeverity":"MEDIUM","cvssVector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:N","cwes":["CWE-367","CWE-918"],"vendors":[],"products":[],"references":[{"url":"https://github.com/Bubka/2FAuth/commit/52e9db94f2da2a6231d77c49537d6d88ce948ee1","tags":[]},{"url":"https://github.com/Bubka/2FAuth/releases/tag/v8.0.0","tags":[]},{"url":"https://github.com/Bubka/2FAuth/security/advisories/GHSA-22mh-gmrh-gpwg","tags":[]},{"url":"https://github.com/Bubka/2FAuth/security/advisories/GHSA-22mh-gmrh-gpwg","tags":[]}],"exploitRefs":[{"url":"https://github.com/Bubka/2FAuth/commit/52e9db94f2da2a6231d77c49537d6d88ce948ee1","tags":[]},{"url":"https://github.com/Bubka/2FAuth/releases/tag/v8.0.0","tags":[]},{"url":"https://github.com/Bubka/2FAuth/security/advisories/GHSA-22mh-gmrh-gpwg","tags":[]},{"url":"https://github.com/Bubka/2FAuth/security/advisories/GHSA-22mh-gmrh-gpwg","tags":[]}],"hasPoc":true,"ai":null}