SSRF in Jgraph Drawio

CVE-2026-63334

draw.io is a configurable diagramming and whiteboarding application. Prior to version 30.2.7, deployments with ENABLE_DRAWIO_PROXY=1 are vulnerable to server-side request forgery because src/main/java/com/mxgraph/online/Utils.java performs the private-address check in Utils.sanitizeUrl() using one DNS resolution, while src/main/java/com/mxgraph/online/ProxyServlet.java later calls URL.openConnection() and performs a second resolution. An attacker-controlled hostname can resolve to a public address during validation and then to a private, link-local, or cloud metadata address when the connection is opened. Successful exploitation can return cloud instance metadata or responses from internal HTTP services through the proxy. This issue is fixed in version 30.2.7.

Vulnerability class: TOCTOU (Time-of-Check to Time-of-Use)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.8 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.003 (24.5th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 24th percentile — 24.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-63334: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-63334?
CVE-2026-63334 is a medium-severity vulnerability in Jgraph Drawio, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 6.8/10. Published 2026-09-21.
How severe is CVE-2026-63334?
Medium severity. CVSS v3 base score is 6.8 out of 10.