SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAwaiting Analysis

CVE-2026-111059

From 3.0.0 until 3.2.11, mr.Markdown converts attacker-controlled Markdown to HTML without sanitizing raw HTML before assigning it to an ipywidgets.HTML sink.

MEDIUM 6.1EPSS 0.28%

Does this matter?

Lower severity and a low EPSS score (0.28%). Track it; it rarely justifies an emergency change on its own.

Description

Mercury is a Python framework for sharing Jupyter notebooks as web applications and dashboards. From 3.0.0 until 3.2.11, mr.Markdown converts attacker-controlled Markdown to HTML without sanitizing raw HTML before assigning it to an ipywidgets.HTML sink. Event-handler attributes and other active HTML can therefore reach the DOM and execute when another user views the application. This issue is fixed in version 3.2.11.

CVSS 3.1
6.1 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
EPSS
0.28% probability · 21th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-79, CWE-116
Source
security-advisories@github.com
EPSS trend
0%3%5%20 October 2026: 0.28%26 October 2026: 0.28%20 October 202626 October 2026

EPSS moved from 0.3% on 20 October 2026 to 0.3% on 26 October 2026.

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