SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAwaiting Analysis

CVE-2026-111058

Prior to 3.2.6, default tokenless deployments allow anonymous clients to create Jupyter kernels and send execute_request messages containing arbitrary Python.

CRITICAL 9.8EPSS 0.52%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.52%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1
9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
0.52% probability · 44th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-862
Source
security-advisories@github.com
EPSS trend
0%3%5%20 October 2026: 0.44%27 October 2026: 0.52%20 October 202627 October 2026

EPSS moved from 0.4% on 20 October 2026 to 0.5% on 27 October 2026.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.