How severe is CVE-2026-44400?

CVE-2026-44400 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-44400 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-44400?

CVE-2026-44400 affects Mailenable. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-44400?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-44400 have an EU (EUVD) identifier?

Yes. CVE-2026-44400 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-28827.

When was CVE-2026-44400 published?

CVE-2026-44400 was published on 2026-05-08 and last updated on 2026-06-17.

CVE-2026-44400

CVE-2026-44400 is a high-severity vulnerability in Mailenable with a CVSS 3.x base score of 8.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-639.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v4: 8.7
EPSS exploit prediction: 0% (27th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-28827
Weakness: CWE-639
Affected product: Mailenable
Published: 2026-05-08
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2026-44400?: CVE-2026-44400 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-44400 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-44400?: CVE-2026-44400 affects Mailenable. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-44400?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-44400 have an EU (EUVD) identifier?: Yes. CVE-2026-44400 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-28827.
When was CVE-2026-44400 published?: CVE-2026-44400 was published on 2026-05-08 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:mailenable:mailenable:*:*:*:*:enterprise_premium:*:*:*

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