SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-34834

This allowed unauthenticated attackers to bypass security checks and access/modify user settings via the /api/settings endpoint by providing arbitrary headers.

HIGH 8.7EPSS 0.25%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.25%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 4.0
8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS
0.25% probability · 17th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-287
Affected
bulwarkmail/webmail
Source
security-advisories@github.com
EPSS trend
0%3%5%26 October 2026: 0.25%26 October 202626 October 2026

EPSS 0.3% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.