{"id":"CVE-2026-113728","state":"PUBLISHED","title":"Bulwark Webmail: DNS-rebinding SSRF in public iCalendar fetch endpoint","description":"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.","publishedAt":"2026-10-20T21:12:38.182Z","updatedAt":"2026-10-27T13:28:01.863Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["bulwarkmail webmail"],"affected":[{"vendor":"bulwarkmail","product":"webmail","versions":[{"version":"< 1.9.2","status":"affected"}]}],"references":["https://github.com/bulwarkmail/webmail/security/advisories/GHSA-24w9-8r42-8jwm","https://github.com/bulwarkmail/webmail/commit/3288589e5248dcc1da769cc578827a9ee1adc941","https://github.com/bulwarkmail/webmail/releases/tag/1.9.2"],"weaknesses":["CWE-918"],"ingestedAt":"2026-10-29T20:10:43.281Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/113xxx/CVE-2026-113728.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-113728","state":"PUBLISHED","datePublished":"2026-10-20T21:12:38.182Z","dateUpdated":"2026-10-27T13:28:01.863Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-10-20T16:03:14.864Z"},"containers":{"cna":{"title":"Bulwark Webmail: DNS-rebinding SSRF in public iCalendar fetch endpoint","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"bulwarkmail","product":"webmail","versions":[{"version":"< 1.9.2","status":"affected"}]}],"references":[{"url":"https://github.com/bulwarkmail/webmail/security/advisories/GHSA-24w9-8r42-8jwm","name":"https://github.com/bulwarkmail/webmail/security/advisories/GHSA-24w9-8r42-8jwm","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/bulwarkmail/webmail/commit/3288589e5248dcc1da769cc578827a9ee1adc941","name":"https://github.com/bulwarkmail/webmail/commit/3288589e5248dcc1da769cc578827a9ee1adc941","tags":["x_refsource_MISC"]},{"url":"https://github.com/bulwarkmail/webmail/releases/tag/1.9.2","name":"https://github.com/bulwarkmail/webmail/releases/tag/1.9.2","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-918","lang":"en","description":"CWE-918: Server-Side Request Forgery (SSRF)","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-10-20T21:12:38.182Z"},"source":{"advisory":"GHSA-24w9-8r42-8jwm","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-10-27T13:27:53.414451Z","id":"CVE-2026-113728","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-27T13:28:01.863Z"}}]}}}