CVE-2026-33678

CVE-2026-33678 is a high-severity vulnerability in Vikunja with a CVSS 3.x base score of 8.1. 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-639.

Key facts

Description

Vikunja is an open-source self-hosted task management platform. Prior to version 2.2.1, `TaskAttachment.ReadOne()` queries attachments by ID only (`WHERE id = ?`), ignoring the task ID from the URL path. The permission check in `CanRead()` validates access to the task specified in the URL, but `ReadOne()` loads a different attachment that may belong to a task in another project. This allows any authenticated user to download or delete any attachment in the system by providing their own accessible task ID with a target attachment ID. Attachment IDs are sequential integers, making enumeration trivial. Version 2.2.1 patches the issue.

Frequently asked questions

What is CVE-2026-33678?
Vikunja is an open-source self-hosted task management platform. Prior to version 2.2.1, `TaskAttachment.ReadOne()` queries attachments by ID only (`WHERE id = ?`), ignoring the task ID from the URL path. The permission check in `CanRead()` validates access to the task specified in the URL, but `ReadOne()` loads a different attachment that may belong to a task in another project. This allows any authenticated user to download or delete any attachment in the system by providing their own accessible task ID with a target attachment ID. Attachment IDs are sequential integers, making enumeration trivial. Version 2.2.1 patches the issue.
How severe is CVE-2026-33678?
CVE-2026-33678 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2026-33678 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-33678?
CVE-2026-33678 affects Vikunja. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-33678?
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-2026-33678 have an EU (EUVD) identifier?
Yes. CVE-2026-33678 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-14921.
When was CVE-2026-33678 published?
CVE-2026-33678 was published on 2026-03-24 and last updated on 2026-06-17.

References

Affected products (1)

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