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TI-2025-40974 Aliases CVE-2025-66563

Monkeytype vulnerable to stored XSS in approve quotes page

Priority HIGH 70CWE-79Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Passive
Attack complexity
Low
Attack requirements
None
Impact type
Cross-site scripting
Confidentiality · integrity · availability
High · Low · None
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-79.

Summary

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).

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00256 17th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
monkeytypegamemonkeytypeup to 25.49.0—No fix listedCNA
  • monkeytype Vendormonkeytypegame Affected up to 25.49.0 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:monkeytype:monkeytype:*:*:*:*:*:*:*:*up to 25.49.0Vulnerablemonkeytypegame
  • cpe:2.3:a:monkeytype:monkeytype:*:*:*:*:*:*:*:* Versions up to 25.49.0 Vulnerable ·monkeytypegame

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-66563

References

Exploit 1

Patch 1

  • TI-2024-27479 Injection in monkeytypegame monkeytype CVSS 3.1CRITICAL 9.6
  • TI-2025-37277 Monkeytype Vulnerable to Self-XSS on loading saved custom text CVSS 4.0LOW 2.4

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences