Auth bypass in Eclipse Milo

CVE-2026-58080

In Eclipse Milo versions 1.0.0 through 1.1.4, `OpcUaServerConfig.copy()` fails to preserve a configured `RoleMapper`. On servers that rely on role permissions and construct the running configuration through `copy()`, sessions receive no role IDs and the default access controller skips role-permission checks, allowing an anonymous client where anonymous sessions are permitted to read role-permission metadata, invoke protected methods, or delete protected nodes.

Vulnerability class: Broken Access Control

EPSS: 0.003 (20.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-58080?
CVE-2026-58080 is a high-severity vulnerability in Eclipse Milo, classified under Missing Authorization. CVSS score: 8.2/10. Published 2026-08-04.
How severe is CVE-2026-58080?
High severity. CVSS v3 base score is 8.2 out of 10.