Privilege escalation in Apache Software Foundation Syncope

CVE-2026-78330

Incorrect privilege assignment vulnerability in Apache Syncope. When the configured JWKS settings for internal JWT authentication are disclosed (at least protocol and key), an attacker can obtain admin privileges after completing a successful authentication and obtaining a valid low-privileges JWT. 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.

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: 0.006 (50.7th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 51st percentile — 50.7% 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-2026-78330: held from 0.006 to 0.006.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-78330?
CVE-2026-78330 is a critical-severity vulnerability in Apache Software Foundation Syncope, classified under Incorrect Privilege Assignment. CVSS score: 9.8/10. Published 2026-09-14.
How severe is CVE-2026-78330?
Critical severity. CVSS v3 base score is 9.8 out of 10.