OAuth session misbinding via skipped state validation
Published Sep 21, 2026 · Updated Sep 21, 2026
OAuth CSRF in draw.io before 30.2.7 allows remote attackers to bind a victim's self-hosted session to the attacker's cloud identity. AbsAuth.java skips comparing stateToken with cookieToken when IS_GAE is false, so Docker and WAR callbacks accept an unbound authorization code. Exploitation requires an enabled cloud integration and victim interaction; resulting actions use the attacker's identity without exposing existing victim files.
Summary
What happened
OAuth CSRF in draw.io before 30.2.7 allows remote attackers to bind a victim's self-hosted session to the attacker's cloud identity. AbsAuth.java skips comparing stateToken with cookieToken when IS_GAE is false, so Docker and WAR callbacks accept an unbound authorization code. Exploitation requires an enabled cloud integration and victim interaction; resulting actions use the attacker's identity without exposing existing victim files.
The record
- CVE
- CVE-2026-63373
- Published
- Sep 21, 2026
- Updated
- Sep 21, 2026
- Vendor
- draw.io Ltd
- Product
- draw.io
- Classifications
- T1204.001
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 21, 2026CVE publishedPublication date reported by the CVE source.
- Sep 21, 2026Record 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.
- Affected versionversion=< 30.2.7
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
Public exploit references
- Upstream OAuth code-injection proof of conceptproof of concept · demonstrated
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
Get started to see how Hinoki identifies affected software and validates exploitability in your environment.
Get started