How severe is CVE-2026-26079?

CVE-2026-26079 has a CVSS 3.x base score of 4.7, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2026-26079 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-26079?

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

Does CVE-2026-26079 have an EU (EUVD) identifier?

Yes. CVE-2026-26079 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-5945.

When was CVE-2026-26079 published?

CVE-2026-26079 was published on 2026-02-11 and last updated on 2026-06-17.

CVE-2026-26079

CVE-2026-26079 is a medium-severity vulnerability with a CVSS 3.x base score of 4.7. 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-829.

Key facts

Severity: Medium (CVSS 3.x base score 4.7)
EPSS exploit prediction: 0% (21st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-5945
Weakness: CWE-829
Published: 2026-02-11
Last modified: 2026-06-17

Description

Roundcube Webmail before 1.5.13 and 1.6 before 1.6.13 allows Cascading Style Sheets (CSS) injection, e.g., because comments are mishandled.

Frequently asked questions

What is CVE-2026-26079?: Roundcube Webmail before 1.5.13 and 1.6 before 1.6.13 allows Cascading Style Sheets (CSS) injection, e.g., because comments are mishandled.
How severe is CVE-2026-26079?: CVE-2026-26079 has a CVSS 3.x base score of 4.7, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2026-26079 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-26079?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-26079 have an EU (EUVD) identifier?: Yes. CVE-2026-26079 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-5945.
When was CVE-2026-26079 published?: CVE-2026-26079 was published on 2026-02-11 and last updated on 2026-06-17.

References

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