CVE-2026-44400

HighPublic PoCUpdated

Published: 08 May 2026

Published

08 May 2026

Modified

01 June 2026

KEV Added

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Patch

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CVSS Score v4 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS Score 0.0035 26.9th percentile

Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2026-44400 is a high-severity Authorization Bypass Through User-Controlled Key (CWE-639) vulnerability in Mailenable Mailenable. Its CVSS base score is 8.7 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 26.9th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

OWASP Top 10 for Web (2025)

EU & UK References

🇪🇺 ENISA EUVD: EUVD-2026-28827

Vulnerability details

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.

CWE(s): CWE-639

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access

Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.

attack.mitre.org →

T1078 Valid Accounts Stealth

Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.

attack.mitre.org →

Why these techniques?

Auth bypass via token replay on public web admin portal directly enables T1190 (public-facing app exploitation) and T1078 (valid account/session abuse).

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0