Auth bypass in Mailenable
CVE-2026-44400
MailEnable Enterprise Premium 10.55 and earlier contains an improper authorization vulnerability in the WebAdmin mobile portal that allows attackers to bypass authentication checks by reusing AuthenticationToken cookies generated for low-privileged users. Attackers can obtain a token from the WebMail login endpoint using the PersistentLogin parameter and replay it against the WebAdmin portal to perform highly privileged administrative actions.
Vulnerability class: IDOR (Insecure Direct Object Reference)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.006 (47.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 47th percentile — 47.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.006 · change: +0.003
Affected products
- Mailenable
- Mailenable Enterprise Premium — versions 0
Weakness classification (CWE)
References
- www.mailenable.com/Premium-ReleaseNotes.txt (release-notes, Release Notes)
- www.vulncheck.com/advisories/mailenable-enterprise-premium-authorization-bypass… (Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2026-44400?
- CVE-2026-44400 is a high-severity vulnerability in Mailenable, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 8.1/10. Published 2026-05-08.
- How severe is CVE-2026-44400?
- High severity. CVSS v3 base score is 8.1 out of 10.