Vulnerability · Published Sep 21, 2026 · Assigned by GitHub_M

CVE-2026-63334draw.io: SSRF via DNS rebinding in ProxyServlet bypasses private IP blocklist

Medium 6.8

In plain English

A medium-severity server-side request forgery in drawio from jgraph. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 25% of all known vulnerabilities).

Severity (CVSS 3.1)6.8Medium

Exploit odds (30 days)0.3%top 75.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

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.

Affected products (as reported)

Vendor	Product	Versions
jgraph	drawio	< 30.2.7

Weakness: CWE-918, CWE-367 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N

References

https://github.com/jgraph/drawio/security/advisories/GHSA-3v4h-8r2c-m8c5 x_refsource_CONFIRM
https://github.com/jgraph/drawio/commit/650fbd742814f6502f78248dc2d8e2aaa5e42b5e x_refsource_MISC
https://github.com/jgraph/drawio/releases/tag/v30.2.7 x_refsource_MISC