SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-63373

An attacker can provide an authorization code for the attacker's cloud-storage identity and induce a victim to visit a callback URL, causing the victim's draw.io session to become authenticated as the attacker identity without a valid state binding.

MEDIUM 4.2EPSS 0.15%

Does this matter?

Lower severity and a low EPSS score (0.15%). Track it; it rarely justifies an emergency change on its own.

Description

draw.io is a configurable diagramming and whiteboarding application. Prior to version 30.2.7, the OAuth callback handler in src/main/java/com/mxgraph/online/AbsAuth.java skips comparison of stateToken and cookieToken whenever IS_GAE is false, which affects self-hosted Docker and WAR deployments. An attacker can provide an authorization code for the attacker's cloud-storage identity and induce a victim to visit a callback URL, causing the victim's draw.io session to become authenticated as the attacker identity without a valid state binding. The shared handler affects Google Drive, OneDrive, GitHub, GitLab, and Dropbox integrations. The victim can then unknowingly perform cloud-storage actions under the attacker's identity, causing session integrity loss and misattribution, but the identity binding does not itself grant access to existing victim cloud files. This issue is fixed in version 30.2.7.

CVSS 3.1
4.2 MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N
EPSS
0.15% probability · 4th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-352
Source
security-advisories@github.com
EPSS trend
0%3%5%22 September 2026: 0.13%26 October 2026: 0.15%22 September 202626 October 2026

EPSS moved from 0.1% on 22 September 2026 to 0.2% on 26 October 2026.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.