CVE-2026-55433

Coder: Devcontainer recreate endpoint missing write authorization allows read-only roles to destroy containers

The devcontainer recreate endpoint relied on route middleware that checked only ActionRead on the workspace and, unlike the sibling delete endpoint, performed no ActionUpdate check before triggering the destructive rebuild.

Note: Exploitation requires an existing low-privilege role with access to the target workspace.

Workarounds

None.

Resources

• Fix: #25812

Credits

Coder would like to thank Anthropic's Security Team (ANT-2026-22454) for independently disclosing this issue!

Any authenticated principal with read-only workspace access, such as a Template Admin or Org Template Admin, could recreate a devcontainer, destroying uncommitted in-container state and, if called repeatedly, denying service. This is an authorization bypass leading to data loss and denial of service.

The application does not perform an authorization check before performing a sensitive operation. Typical impact: unauthorized access to restricted functionality or data.

CVE-2026-55433 has a CVSS score of 5.4 (Medium). The vector is network-reachable, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (2.34.2, 2.33.8, 2.32.7, 2.29.17); upgrading removes the vulnerable code path.

Kodem intelligence

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The fix adds an explicit ActionUpdate authorization check before the agent is dialed like the delete endpoint.

The fix was backported to all supported release lines:

1. What is CVE-2026-55433? CVE-2026-55433 is a medium-severity missing authorization vulnerability in github.com/coder/coder/v2 (go), affecting versions >= 2.34.0, < 2.34.2. It is fixed in 2.34.2, 2.33.8, 2.32.7, 2.29.17. The application does not perform an authorization check before performing a sensitive operation.
2. How severe is CVE-2026-55433? CVE-2026-55433 has a CVSS score of 5.4 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of github.com/coder/coder/v2 are affected by CVE-2026-55433? github.com/coder/coder/v2 (go) versions >= 2.34.0, < 2.34.2 is affected.
4. Is there a fix for CVE-2026-55433? Yes. CVE-2026-55433 is fixed in 2.34.2, 2.33.8, 2.32.7, 2.29.17. Upgrade to this version or later.
5. Is CVE-2026-55433 exploitable, and should I be worried? Whether CVE-2026-55433 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
6. What actually determines whether CVE-2026-55433 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.
7. How do I fix CVE-2026-55433?
   • Upgrade github.com/coder/coder/v2 to 2.34.2 or later
   • Upgrade github.com/coder/coder/v2 to 2.33.8 or later
   • Upgrade github.com/coder/coder/v2 to 2.32.7 or later
   • Upgrade github.com/coder/coder/v2 to 2.29.17 or later

Other vulnerabilities in github.com/coder/coder/v2