Quick answers
- Is CVE-2026-63373 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-63373 being exploited in the wild.
- How severe is CVE-2026-63373?
- Medium severity, with a CVSS score of 4.2, published 21 September 2026.
- Which products and versions are affected?
- JGraph Draw.Io before 30.2.7.
- Is there a fix for CVE-2026-63373?
- A patch was published on 2026-06-30. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-63373 attacked?
- It is attacked over the network, in a web application.
- Am I affected by CVE-2026-63373?
- Check whether you run JGraph Draw.Io at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
The vulnerability exists in the OAuth callback handler (AbsAuth.java) which skips state token validation when IS_GAE is false, a condition met in self-hosted Docker and WAR deployments. An attacker can redirect a victim to a callback URL with an authorization code from the attacker's cloud identity, and without state validation, the victim's session becomes bound to the attacker's cloud account. The attack requires user interaction (victim visiting a malicious link) but no authentication prerequisites.
Affected products
- JGraph draw.io before 30.2.7
Timeline
- 2026-09-21: disclosed
- 2026-06-30: patched