Is CVE-2026-111058 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-111058 being exploited in the wild.

How severe is CVE-2026-111058?

Critical severity, with a CVSS score of 9.8, published 19 October 2026.

Which products and versions are affected?

Mljar Mercury prior to 3.2.6; mercury (PyPI) <= 3.2.5, ECOSYSTEM:introduced=0,fixed=3.2.6.

Is there a fix for CVE-2026-111058?

Yes. mercury (PyPI): upgrade to 3.2.6 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-111058 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-111058?

Check whether you run Mljar Mercury or mercury (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-111058: Mercury framework arbitrary code execution in anonymous kernels

Q: Is there a fix for CVE-2026-111058?

Yes. mercury (PyPI): upgrade to 3.2.6 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-111058 attacked?

It is attacked over the network, in a software library.

Q: Am I affected by CVE-2026-111058?

Check whether you run Mljar Mercury or mercury (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-111058 · Severity: critical · CVSS 9.8 · Published 2026-10-19

Mercury is a Python framework that converts Jupyter notebooks into shareable web applications. Prior to version 3.2.6, deployments without authentication enabled allowed anyone on the network to create Jupyter kernel sessions and execute arbitrary Python code on the server, potentially leading to full system compromise.

Technologies: Mljar Mercury, mercury (PyPI). Vendors: Mljar, PyPI.

Quick answers

Is CVE-2026-111058 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-111058 being exploited in the wild.
How severe is CVE-2026-111058?: Critical severity, with a CVSS score of 9.8, published 19 October 2026.
Which products and versions are affected?: Mljar Mercury prior to 3.2.6; mercury (PyPI) <= 3.2.5, ECOSYSTEM:introduced=0,fixed=3.2.6.
Is there a fix for CVE-2026-111058?: Yes. mercury (PyPI): upgrade to 3.2.6 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-111058 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-111058?: Check whether you run Mljar Mercury or mercury (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

mercury (PyPI): upgrade to 3.2.6 or later
```
pip install "mercury>=3.2.6"
```

Technical details

The vulnerability exists in tokenless Mercury deployments where the endpoint blocklist failed to restrict access to /api/kernels and the WebSocket wrapper did not validate authorization on execute_request messages. An unauthenticated network attacker can directly create kernel sessions and send arbitrary Python code for execution without authentication, gaining remote code execution on the underlying system.

Affected products

mljar Mercury prior to 3.2.6

Identifiers

CVE-2026-111058
GHSA-rv4m-xm3f-3ccq

Timeline

2026-10-19: disclosed
2026-08-27: patched

References

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