How severe is CVE-2026-50591?

CVE-2026-50591 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2026-50591 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-50591?

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

Does CVE-2026-50591 have an EU (EUVD) identifier?

Yes. CVE-2026-50591 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-34782.

When was CVE-2026-50591 published?

CVE-2026-50591 was published on 2026-06-05 and last updated on 2026-06-17.

CVE-2026-50591

CVE-2026-50591 is a medium-severity vulnerability with a CVSS 3.x base score of 5.4. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
EPSS exploit prediction: 0% (3rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-34782
Weakness: CWE-79
Published: 2026-06-05
Last modified: 2026-06-17

Description

In Znuny LTS before 6.5.21 and Znuny before 7.3.3, XSS can occur via stored user preferences.

Frequently asked questions

What is CVE-2026-50591?: In Znuny LTS before 6.5.21 and Znuny before 7.3.3, XSS can occur via stored user preferences.
How severe is CVE-2026-50591?: CVE-2026-50591 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2026-50591 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-50591?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-50591 have an EU (EUVD) identifier?: Yes. CVE-2026-50591 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-34782.
When was CVE-2026-50591 published?: CVE-2026-50591 was published on 2026-06-05 and last updated on 2026-06-17.

References

https://www.znuny.org/en/advisories/zsa-2026-11

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