# CVE-2026-5774: Juju API Server Denial of Service and Authentication Replay via Unsynchronized Token Map

> An authenticated user can cause a denial of service or reuse discharge tokens due to unsynchronized token maps in the Juju API server.

- **Severity:** Medium 6.1 (`CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 10 Apr 2026
- **Updated:** 10 Apr 2026
- **Also known as:** GHSA-7m55-2hr4-pw78, GO-2026-5228

## What is CVE-2026-5774?

CVE-2026-5774 is a medium-severity vulnerability in Canonical Juju, published on 10 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

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: CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization)

## Which versions are affected by CVE-2026-5774?

3 open source packages ship an affected version, including github.com/juju/juju. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/juju/juju` | Go | All versions | 0.0.0-20260408003526-d395054dc2c3 |
| `github.com/juju/juju` | Go | All versions | 0.0.0-20260408003526-d395054dc2c3 |
| `github.com/juju/juju` | Go | All versions | 0.0.0-20260408003526-d395054dc2c3 |

Products: Canonical Juju.

## How do I fix CVE-2026-5774?

Upgrade github.com/juju/juju to 0.0.0-20260408003526-d395054dc2c3 or later.

## Is CVE-2026-5774 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-5774 exists.

## Other vulnerabilities in Canonical Juju

- [CVE-2026-4370](https://insights.sbomify.com/CVE-2026-4370/): Improper TLS Client/Server authentication and certificate verification on Database Cluster (critical 10.0)
- [CVE-2026-5412](https://insights.sbomify.com/CVE-2026-5412/): Juju CloudSpec API could leak senstive information (critical 9.9)
- [CVE-2017-9232](https://insights.sbomify.com/CVE-2017-9232/): Juju uses a UNIX domain socket without setting appropriate permissions (critical 9.8)
- [CVE-2026-32693](https://insights.sbomify.com/CVE-2026-32693/): Unauthorized access to Kubernetes secrets in Juju (high 8.8)
- [CVE-2025-0928](https://insights.sbomify.com/CVE-2025-0928/): Arbitrary executable upload via authenticated endpoint (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-5774 and fix it if it is affected.

What it is: CVE-2026-5774 is a medium-severity vulnerability in Canonical Juju, published on 10 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-5774 exists.

Affected packages and fixed versions:
- github.com/juju/juju (Go): affected all versions; fixed in 0.0.0-20260408003526-d395054dc2c3
- github.com/juju/juju (Go): affected all versions; fixed in 0.0.0-20260408003526-d395054dc2c3
- github.com/juju/juju (Go): affected all versions; fixed in 0.0.0-20260408003526-d395054dc2c3

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-5774/ (Markdown: https://insights.sbomify.com/CVE-2026-5774/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-5774
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-5774
- OSV: https://osv.dev/vulnerability/CVE-2026-5774

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-5774/
Summaries are generated and may contain mistakes; the official description above is the record.