CVE-2026-111058 Mercury: Unauthenticated Remote Code Execution via /api/kernels
Unauthenticated attackers can execute arbitrary Python code via the /api/kernels endpoint in default Mercury deployments.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-111058?
CVE-2026-111058 is a critical code injection vulnerability in mljar mercury, published on 19 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Mercury is a Python framework for sharing Jupyter notebooks as web applications and dashboards. Prior to 3.2.6, default tokenless deployments allow anonymous clients to create Jupyter kernels and send execute_request messages containing arbitrary Python. The endpoint blocklist does not cover /api/kernels, and the websocket wrapper previously tracked idle activity without authorizing executable messages. This issue is fixed in version 3.2.6.
Weakness: CWE-862
Which versions are affected by CVE-2026-111058?
2 open source packages ship an affected version, including mercury.
| Package | Affected | Fixed in |
|---|---|---|
mercury PyPI | All versions | 3.2.6 |
mercury PyPI | All versions | 3.2.6 |
How do I fix CVE-2026-111058?
Upgrade mercury to 3.2.6 or later.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-111058 being exploited?
There is no known exploitation of CVE-2026-111058 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Sources
Also known as GHSA-rv4m-xm3f-3ccq.