How severe is CVE-2026-33335?

CVE-2026-33335 has a CVSS 3.x base score of 8.0, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-33335 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-33335?

CVE-2026-33335 affects Vikunja. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-33335?

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-2026-33335 have an EU (EUVD) identifier?

Yes. CVE-2026-33335 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-14909.

When was CVE-2026-33335 published?

CVE-2026-33335 was published on 2026-03-24 and last updated on 2026-06-17.

CVE-2026-33335

CVE-2026-33335 is a high-severity vulnerability in Vikunja with a CVSS 3.x base score of 8.0. 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-939.

Key facts

Severity: High (CVSS 3.x base score 8.0)
CVSS v4: 6.4
EPSS exploit prediction: 0% (16th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-14909
Weakness: CWE-939
Affected product: Vikunja
Published: 2026-03-24
Last modified: 2026-06-17

Description

Vikunja is an open-source self-hosted task management platform. Starting in version 0.21.0 and prior to version 2.2.0, the Vikunja Desktop Electron wrapper passes URLs from `window.open()` calls directly to `shell.openExternal()` without any validation or protocol allowlisting. An attacker who can place a link with `target="_blank"` (or that otherwise triggers `window.open`) in user-generated content can cause the victim's operating system to open arbitrary URI schemes, invoking local applications, opening local files, or triggering custom protocol handlers. Version 2.2.0 patches the issue.

Frequently asked questions

What is CVE-2026-33335?: Vikunja is an open-source self-hosted task management platform. Starting in version 0.21.0 and prior to version 2.2.0, the Vikunja Desktop Electron wrapper passes URLs from `window.open()` calls directly to `shell.openExternal()` without any validation or protocol allowlisting. An attacker who can place a link with `target="_blank"` (or that otherwise triggers `window.open`) in user-generated content can cause the victim's operating system to open arbitrary URI schemes, invoking local applications, opening local files, or triggering custom protocol handlers. Version 2.2.0 patches the issue.
How severe is CVE-2026-33335?: CVE-2026-33335 has a CVSS 3.x base score of 8.0, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-33335 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-33335?: CVE-2026-33335 affects Vikunja. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-33335?: 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-2026-33335 have an EU (EUVD) identifier?: Yes. CVE-2026-33335 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-14909.
When was CVE-2026-33335 published?: CVE-2026-33335 was published on 2026-03-24 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:*

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