How severe is CVE-2026-2748?

CVE-2026-2748 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2026-2748 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-2748?

CVE-2026-2748 affects Seppmail. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-2748?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-2748 have an EU (EUVD) identifier?

Yes. CVE-2026-2748 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-9385.

When was CVE-2026-2748 published?

CVE-2026-2748 was published on 2026-03-04 and last updated on 2026-06-17.

CVE-2026-2748

CVE-2026-2748 is a medium-severity vulnerability in Seppmail with a CVSS 3.x base score of 5.3. 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-295.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v4: 7.8
EPSS exploit prediction: 0% (2nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-9385
Weakness: CWE-295
Affected product: Seppmail
Published: 2026-03-04
Last modified: 2026-06-17

Description

SEPPmail Secure Email Gateway before version 15.0.1 improperly validates S/MIME certificates issued for email addresses containing whitespaces, allowing signature spoofing.

Frequently asked questions

What is CVE-2026-2748?: SEPPmail Secure Email Gateway before version 15.0.1 improperly validates S/MIME certificates issued for email addresses containing whitespaces, allowing signature spoofing.
How severe is CVE-2026-2748?: CVE-2026-2748 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2026-2748 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-2748?: CVE-2026-2748 affects Seppmail. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-2748?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-2748 have an EU (EUVD) identifier?: Yes. CVE-2026-2748 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-9385.
When was CVE-2026-2748 published?: CVE-2026-2748 was published on 2026-03-04 and last updated on 2026-06-17.

References

https://downloads.seppmail.com/extrelnotes/150/ERN15.0.html#seppmail-vulnerability-disclosure

Affected products (1)

cpe:2.3:a:seppmail:seppmail:*:*:*:*:*:*:*:*

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