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Fencer Intel
medium 6.8

CVE-2026-63334 json

draw.io: SSRF via DNS rebinding in ProxyServlet bypasses private IP blocklist

published 4mo ago modified last mo. also EUVD-2026-84007 , GHSA-3v4h-8r2c-m8c5

Unreviewed: the maintainers' own advisory

Published by the maintainers on their GitHub repository jgraph/drawio. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.

cvss
6.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 24%
public exploits
0
none known

Summary

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.

Patch / fix

  • diagrams drawio 30.2.7

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CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
last mo.

Exploit prediction

0.32% chance of exploitation in the next 30 days, higher than 24% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 3.1 6.8 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N

Affected products

  • jgraph drawio

Classification

Weakness
  • CWE-918 Server-Side Request Forgery
  • CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

The maintainers of jgraph/drawio published their own advisory on GitHub. Reviewed sources take precedence over it.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.