CVE-2026-63248: milo Auth Bypass — Fix

Description

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.

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CVSS v3.1 Score

6.5

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

EPSS — Exploit Prediction

0.0016

Probability of exploitation

0.05%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-862 Missing Authorization

Affected Products

Vendor	Product	Versions
eclipse	milo	0.6.0 — 1.1.5

References

Advisories & Patches

https://github.com/eclipse-milo/milo/commit/a5dae1be0657d2b4fcb66e63f377c1dc36069e2a https://gitlab.eclipse.org/security/cve-assignment/-/work_items/181 https://gitlab.eclipse.org/security/vulnerability-reports/-/work_items/598

Frequently Asked Questions

What is 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. It has a CVSS v3.1 base score of 6.5 (MEDIUM).

How severe is CVE-2026-63248? +

CVE-2026-63248 has a CVSS v3.1 score of 6.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0016, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-63248? +

CVE-2026-63248 affects products from eclipse, specifically: milo. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-63248? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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