How severe is CVE-2026-44126?

CVE-2026-44126 has a CVSS 4.0 base score of 9.2, rated critical severity.

Is CVE-2026-44126 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-44126?

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

Does CVE-2026-44126 have an EU (EUVD) identifier?

Yes. CVE-2026-44126 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-28635.

When was CVE-2026-44126 published?

CVE-2026-44126 was published on 2026-05-08 and last updated on 2026-06-17.

CVE-2026-44126

CVE-2026-44126 is a critical-severity vulnerability with a CVSS 4.0 base score of 9.2. 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-502.

Key facts

Severity: Critical (CVSS 4.0 base score 9.2)
EPSS exploit prediction: 0% (37th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-28635
Weakness: CWE-502
Published: 2026-05-08
Last modified: 2026-06-17

Description

SEPPmail Secure Email Gateway before version 15.0.4 insecurely deserializes untrusted data, which can be reached from the new GINA UI and may allow unauthenticated remote attackers to execute code via a crafted serialized object.

Frequently asked questions

What is CVE-2026-44126?: SEPPmail Secure Email Gateway before version 15.0.4 insecurely deserializes untrusted data, which can be reached from the new GINA UI and may allow unauthenticated remote attackers to execute code via a crafted serialized object.
How severe is CVE-2026-44126?: CVE-2026-44126 has a CVSS 4.0 base score of 9.2, rated critical severity.
Is CVE-2026-44126 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-44126?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-44126 have an EU (EUVD) identifier?: Yes. CVE-2026-44126 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-28635.
When was CVE-2026-44126 published?: CVE-2026-44126 was published on 2026-05-08 and last updated on 2026-06-17.

References

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