High 7.5Published Oct 20, 2026

CVE-2026-113728Bulwark Webmail: DNS-rebinding SSRF in public iCalendar fetch endpoint

Updated under an hour ago (2026-10-21 05:00 UTC)

Does this affect you?

It affects bulwarkmail webmail. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

Do this next

Start free and add your stack

Free account, 1 product

Every CVE for bulwarkmail webmail

Exploited in the last 30 days

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.

CVSS: 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Weakness (CWE): CWE-918
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Received
Record last updated: Oct 20, 2026
First seen by InfoSec Signals: Oct 20, 2026

Affected products

Affected products

bulwarkmail webmail bulwarkmail:webmail (from the name)	before 1.9.2	CNA record

References

https://github.com/bulwarkmail/webmail/security/advisories/GHSA-24w9-8r42-8jwmx-refsource-confirm
https://github.com/bulwarkmail/webmail/commit/3288589e5248dcc1da769cc578827a9ee1adc941x-refsource-misc
https://github.com/bulwarkmail/webmail/releases/tag/1.9.2x-refsource-misc

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.