High 7.1Published Dec 4, 2025

CVE-2025-66563Monkeytype vulnerable to stored XSS in approve quotes page

Updated under an hour ago (Oct 27, 2026, 12:10 AM ET)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for monkeytypegame monkeytype

Exploited in the last 30 days

Monkeytype is a minimalistic and customizable typing test. In 25.49.0 and earlier, there is improper handling of user input which allows an attacker to execute malicious javascript on anyone viewing a malicious quote submission. quote.text and quote.source are user input, and they're inserted straight into the DOM. If they contain HTML tags, they will be rendered (after some escaping using quotes and textarea tags).

CVSS: 7.1 HIGH (v4.0, CNA)CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N
Weakness (CWE): CWE-79
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Dec 5, 2025
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

monkeytypegame monkeytype monkeytypegame:monkeytype (from the name)	through 25.49.0	CNA record
monkeytype monkeytype monkeytype:monkeytype	through 25.49.0	NVD

References

References

https://github.com/monkeytypegame/monkeytype/security/advisories/GHSA-mfjh-9552-8g27	x-refsource-confirm, exploit, vendor-advisory
https://github.com/monkeytypegame/monkeytype/commit/d6d062a77132ba7d6ba3b482d46ae329d3b8d695	x-refsource-misc, patch

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.