{"id":"CVE-2026-113728","summary":"Bulwark Webmail: DNS-rebinding SSRF in public iCalendar fetch endpoint","details":"Bulwark Webmail is a self-hosted webmail client for Stalwart Mail Server. Prior to 1.9.2, the unauthenticated POST /api/fetch-ical endpoint validates a caller-supplied hostname with one DNS lookup and then passes the URL to fetch, which performs a separate lookup for the socket connection. An attacker controlling authoritative DNS can return a public address during validation and then rebind the hostname to a loopback, private, link-local, or cloud metadata address for the connection, causing the server to return up to 10 MB of an internal HTTP or HTTPS response. The same check-then-fetch pattern also existed in authenticated JMAP login and TOTP token-exchange flows. This issue is fixed in version 1.9.2.","aliases":["GHSA-24w9-8r42-8jwm"],"modified":"2026-10-21T10:46:16.822682961Z","published":"2026-10-20T21:12:38.182Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/113xxx/CVE-2026-113728.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-918"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/113xxx/CVE-2026-113728.json"},{"type":"FIX","url":"https://github.com/bulwarkmail/webmail/commit/3288589e5248dcc1da769cc578827a9ee1adc941"},{"type":"WEB","url":"https://github.com/bulwarkmail/webmail/releases/tag/1.9.2"},{"type":"ADVISORY","url":"https://github.com/bulwarkmail/webmail/security/advisories/GHSA-24w9-8r42-8jwm"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-113728"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/bulwarkmail/webmail","events":[{"introduced":"0"},{"fixed":"2f1192bb3285dea2c8b8ece461d52967fe0e6706"},{"fixed":"3288589e5248dcc1da769cc578827a9ee1adc941"}],"database_specific":{"extracted_events":[{"source":"AFFECTED_FIELD","strategy":"StringRangeExpression","range":[{"introduced":"0"},{"fixed":"1.9.2"}]},{"range":[{"fixed":"3288589e5248dcc1da769cc578827a9ee1adc941"}],"source":"REFERENCES_COMMIT"},{"range":[{"fixed":"2f1192bb3285dea2c8b8ece461d52967fe0e6706"}],"source":"REFERENCES_TAG","original_tag":"1.9.2"}]}}],"versions":["1.9.1","1.9.0","1.7.1","1.7.0","1.6.7","1.6.6","1.6.5","1.6.4","1.6.3","1.6.2","1.6.1","1.6.0","1.5.4","1.5.3","1.5.2","1.5.1","1.5.0","1.4.14","1.4.11","1.4.10","1.4.9","1.3.9","1.4.8","1.4.7","1.4.6","1.4.5","1.4.4","1.4.3","1.4.2","1.4.0","1.3.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-113728.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"}]}