Vulnerability · Published Apr 2, 2026 · Assigned by GitHub_M

CVE-2026-34834Bulwark Webmail: Authentication Bypass in verifyIdentity() due to missing cookie validation

High 8.7

In plain English

A high-severity improper authentication in webmail from bulwarkmail. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 17% of all known vulnerabilities).

Severity (CVSS 4.0)8.7High

Exploit odds (30 days)0.3%top 82.7% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Bulwark Webmail is a self-hosted webmail client for Stalwart Mail Server. Prior to version 1.4.10, the verifyIdentity() function contained logic that returned true if no session cookies were present. This allowed unauthenticated attackers to bypass security checks and access/modify user settings via the /api/settings endpoint by providing arbitrary headers. This issue has been patched in version 1.4.10.

Affected products (as reported)

Vendor	Product	Versions
bulwarkmail	webmail	< 1.4.10

Weakness: CWE-287 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

References

https://github.com/bulwarkmail/webmail/security/advisories/GHSA-4356-876g-rfmh x_refsource_CONFIRM
https://github.com/bulwarkmail/webmail/releases/tag/1.4.10 x_refsource_MISC