Juju 4.0.5/3.6.20/2.9.56 API: Improper userTokens sync allows DoS or token reuse
CVE-2026-5774 Published on April 10, 2026
Juju API Server Denial of Service and Authentication Replay via Unsynchronized Token Map
Improper synchronization of the userTokens map in the API server in Canonical Juju 4.0.5, 3.6.20, and 2.9.56 may allow an authenticated user to possibly cause a denial of service on the server or possibly reuse a single-use discharge token.
Weakness Type
What is a Race Condition Vulnerability?
The program contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently.
CVE-2026-5774 has been classified to as a Race Condition vulnerability or weakness.
Affected Versions
Canonical Juju:- Version 2.0.0 and below 2.9.57 is affected.
- Version 3.0.0 and below 3.6.21 is affected.
- Version 4.0.0 and below 4.0.6 is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.