CVE-2025-59838Public exploit

Self-XSS via unsanitized custom-text name

Published Sep 25, 2025 · Updated Sep 25, 2025

Stored cross-site scripting in Monkeytype 25.36.0 and earlier allows local users to execute script in their own browser via a saved custom-text name. In modes-notice.ts, jQuery append inserts customTextName directly into an HTML template without neutralizing markup. Exploitation requires saving and loading a long custom text with a crafted name, and the script affects only the creator's browser context.

CVSS severity2.4
Low
EPSS probability0.23%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored cross-site scripting in Monkeytype 25.36.0 and earlier allows local users to execute script in their own browser via a saved custom-text name. In modes-notice.ts, jQuery append inserts customTextName directly into an HTML template without neutralizing markup. Exploitation requires saving and loading a long custom text with a crafted name, and the script affects only the creator's browser context.

The record

CVE
CVE-2025-59838
Published
Sep 25, 2025
Updated
Sep 25, 2025
Vendor
Monkeytype
Product
Monkeytype
Classifications
CWE-79, T1059.007
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Sep 25, 2025CVE publishedPublication date reported by the CVE source.
  2. Sep 25, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< f025b121cbe437e29de432b4aa72e0de22c755b7

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

Monkeytype · Monkeytypeversion=< f025b121cbe437e29de432b4aa72e0de22c755b7

Published CVSS scores

5.4NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
2.4GitHubCVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007JavaScript/JScript

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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