Summary
Vikunja: Read-only project members can obtain any link share's access hash via the single-share read endpoint (v1 and v2) and escalate to the share's permission level
Impact
Broken access control / privilege escalation within shared projects (CWE-862, CWE-639: the link-share hash is a bearer capability disclosed to a lesser-privileged member; CWE-200 for the information exposure). Any read-level member of a project that has a link share can escalate to that share's permission level: write members' tasks/comments can be created and modified; an admin-level share additionally grants project settings and share management for the project. Confidentiality is also affected insofar as the hash itself is the project's shared secret. Suggested fix: require project.IsAdmin in LinkSharing.CanRead (aligning with ReadAll), or omit the hash field from responses to non-admin members.
The application does not perform an authorization check before performing a sensitive operation. Typical impact: unauthorized access to restricted functionality or data.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is CVE-2026-91985? CVE-2026-91985 is a high-severity missing authorization vulnerability in code.vikunja.io/api (go), affecting versions <= 2.5.0. It is fixed in 2.6.0. The application does not perform an authorization check before performing a sensitive operation.
- Which versions of code.vikunja.io/api are affected by CVE-2026-91985? code.vikunja.io/api (go) versions <= 2.5.0 is affected.
- Is there a fix for CVE-2026-91985? Yes. CVE-2026-91985 is fixed in 2.6.0. Upgrade to this version or later.
- Is CVE-2026-91985 exploitable, and should I be worried? Whether CVE-2026-91985 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-91985 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-91985? Upgrade
code.vikunja.io/apito 2.6.0 or later.