CVE-2025-66563

Monkeytype vulnerable to stored XSS in approve quotes page

MEDIUM
6.1
CVSS Score
Published: December 4, 2025 at 10:34 PM UTC
Updated: October 18, 2026 at 03:10 PM UTC
2 products affected across 2 vendorsMonkeytypeMonkeytype

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Severity
MEDIUM6.1
Exploit prediction
EPSS 0.2%
SSVC
PoC

Description

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).

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCPoCAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-79

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