Auth bypass in Eclipse Milo
CVE-2026-63248
In Eclipse Milo versions 0.6.0 through 1.1.4, OPC UA server diagnostics nodes do not enforce access authorization. An anonymous client can enable diagnostics over a None/None endpoint without a certificate; with a trusted client application certificate over SignAndEncrypt, it can read security diagnostics for other active sessions, exposing usernames, login history, authentication mechanisms, security modes and policies, and public client certificates.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (17.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 18th percentile — 17.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
- Eclipse Milo
- Eclipse Foundation Milo — versions 0.6.0
Weakness classification (CWE)
References
- github.com/eclipse-milo/milo/commit/a5dae1be0657d2b4fcb66e63f377c1dc36069e2a (Patch)
- gitlab.eclipse.org/security/vulnerability-reports/-/work_items/598 (Issue Tracking, Vendor Advisory)
- gitlab.eclipse.org/security/cve-assignment/-/work_items/181 (Patch, Issue Tracking, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-63248?
- CVE-2026-63248 is a medium-severity vulnerability in Eclipse Milo, classified under Missing Authorization. CVSS score: 6.5/10. Published 2026-08-04.
- How severe is CVE-2026-63248?
- Medium severity. CVSS v3 base score is 6.5 out of 10.