CVE-2025-62670Public exploitNetwork attack vector

Browser script execution via unsafe system-message rendering

Published Oct 18, 2025 · Updated Oct 20, 2025

Stored XSS in Flex Diagrams master allows remote attackers to execute browser script through a crafted Drawio diagram-edit request. ext.flexdiagrams.drawio.js retrieves flexdiagrams-drawio-saveinfo as text but passes it to OO.ui.HtmlSnippet, causing message markup to be interpreted as HTML. Exploitation requires an existing Drawio page and an editdiagram request selecting the x-xss language; the script runs in the wiki origin and can access data or perform actions available to that browser context.

CVSS severity6.9
Medium
EPSS probability0.42%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Stored XSS in Flex Diagrams master allows remote attackers to execute browser script through a crafted Drawio diagram-edit request. ext.flexdiagrams.drawio.js retrieves flexdiagrams-drawio-saveinfo as text but passes it to OO.ui.HtmlSnippet, causing message markup to be interpreted as HTML. Exploitation requires an existing Drawio page and an editdiagram request selecting the x-xss language; the script runs in the wiki origin and can access data or perform actions available to that browser context.

The record

CVE
CVE-2025-62670
Published
Oct 18, 2025
Updated
Oct 20, 2025
Vendor
Wikimedia Foundation
Product
Flex Diagrams
Classifications
CWE-79, CAPEC-592
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 18, 2025CVE publishedPublication date reported by the CVE source.
  2. Oct 20, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=master

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Wikimedia Foundation · Flex Diagramsversion=master

Published CVSS scores

6.9Wikimedia FoundationCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L

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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CAPEC-592Stored XSS

Public exploit references

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

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo