Is This vulnerability exploited in the wild?

No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

How severe is This vulnerability?

Medium severity, with a CVSS score of 4.3, published 15 September 2026.

Which products and versions are affected?

code.vikunja.io/api (Go) >= 1.0.0, <= 2.5.0; Vikunja API 1.0.0 to 2.5.0.

Is there a fix for This vulnerability?

Yes: fixed in 2.6.0. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is This vulnerability attacked?

It is attacked over the network, in a software library.

Check whether you run code.vikunja.io/api (Go) or Vikunja API at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Vikunja API token scope bypass via task expand parameter

Q: Is there a fix for This vulnerability?

Yes: fixed in 2.6.0. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is This vulnerability attacked?

It is attacked over the network, in a software library.

Q: Am I affected?

Check whether you run code.vikunja.io/api (Go) or Vikunja API at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Severity: medium · CVSS 4.3 · Published 2026-09-15

Vikunja is a task and project management application with an API that uses tokens with granular permission scopes. A vulnerability allows attackers with limited token scopes to bypass authorization checks by using query parameters to expand and access restricted data like task comments, reactions, and time entry counts that the token should not permit.

Technologies: code.vikunja.io/api (Go), Vikunja API. Vendors: Go, Vikunja.

Quick answers

Is This vulnerability exploited in the wild?: No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.
How severe is This vulnerability?: Medium severity, with a CVSS score of 4.3, published 15 September 2026.
Which products and versions are affected?: code.vikunja.io/api (Go) >= 1.0.0, <= 2.5.0; Vikunja API 1.0.0 to 2.5.0.
Is there a fix for This vulnerability?: Yes: fixed in 2.6.0. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is This vulnerability attacked?: It is attacked over the network, in a software library.
Am I affected?: Check whether you run code.vikunja.io/api (Go) or Vikunja API at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Fixed in: 2.6.0

Technical details

The vulnerability exists in Vikunja's API token authorization layer (models.CanDoAPIRoute) which only checks HTTP method and route path, ignoring query string parameters. Task read endpoints accept an expand parameter that embeds data from other permission groups (comments, reactions, time_entries) without verifying the token holds those scopes. An attacker with a token scoped only to tasks:read can use expand=comments or expand=reactions to retrieve restricted data that direct API calls to /comments or /reactions endpoints would deny.

Affected products

Vikunja API 1.0.0 to 2.5.0

Timeline

2026-08-31: disclosed
2026-09-15: advisory

References

https://github.com/go-vikunja/vikunja/security/advisories/GHSA-9rg3-v78m-26q8

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