Auth bypass in Apache Software Foundation Syncope

CVE-2026-77181

Incorrect Authorization vulnerability in Apache Syncope. An administrator with ClientApp's update entitlement is unable to perform the related operation, while ClientApp's create entitlement is checked both for create and update operations on ClientApp. This issue affects Apache Syncope: from 3.0.0-M0 through 3.0.16, from 4.0.0-M0 Through 4.0.7, from 4.1.0-M0 through 4.1.2. Users are recommended to upgrade to version 4.0.8 / 4.1.3, which fix this issue.

Vulnerability class: Broken Access Control

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.005 (43.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 44th percentile — 43.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-77181: held from 0.005 to 0.005.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-77181?
CVE-2026-77181 is a critical-severity vulnerability in Apache Software Foundation Syncope, classified under Incorrect Authorization. CVSS score: 9.8/10. Published 2026-09-14.
How severe is CVE-2026-77181?
Critical severity. CVSS v3 base score is 9.8 out of 10.