CVE-2017-16876

What it is

Cross-site scripting (XSS) vulnerability in the _keyify function in mistune.py in Mistune before 0.8.1 allows remote attackers to inject arbitrary web script or HTML by leveraging failure to escape the "key" argument.

At a glance

Exploitability

Can be exploited over the network without logging in, but needs a user to act. Limited direct impact.

Exploit odds

2.2% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2017-12-29 15:29 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 01:10 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 2.2% in the next 30 days (EPSS).
• Severity: 6.1 MEDIUM (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2017-12-29 15:29 UTC

Last modified

2026-06-17 01:10 UTC

Exploit probability

2.2% · EPSS, next 30 days

Weakness

CWE-79 · Cross-site scripting

Record status

Modified

Affected

• Mistune Project Mistune < 0.8.1
• Fedoraproject Fedora 26

Attack profile CVSS 3.0 · 6.1

Attack vector

Network

Complexity

Low

Privileges needed

None

User interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2017-16876.md and follow it. Check whether this project is affected by CVE-2017-16876. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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