Answer in brief
CVE-2026-113728 records a High severity (CVSS 7.5) vulnerability in Bulwark Webmail: DNS-rebinding SSRF in public iCalendar fetch endpoint. The current sources do not mark it as known exploited. The current feed maps bulwarkmail/webmail (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps bulwarkmail/webmail (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| bulwarkmail/webmailgeneric | <1.9.2 | 1.9.2 |
Published upstream
Oct 20, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 20, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 21, 2026
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.
Quoted source text, attributed separately from HOL analysis.