# CVE-2026-78330 — Apache Syncope

> As of 2026-09-14, CVE-2026-78330 is a CRITICAL-severity vulnerability in Apache Syncope, CVSS v3.1 9.8, EPSS 0.6% (49.2th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-78330, most recently “September 2026 Microsoft Patch Tuesday — Record 966+ Vulnerabilities with Two Actively Exploited Zero-Days (CVE-2026-81963, CVE-2026-85880) and Multiple Critical Wormable RCEs”.

**Last updated:** 2026-09-14

## What is 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.

The record classifies CVE-2026-78330 under weakness class [CWE-266](https://intel.threadlinqs.com/cwe/CWE-266). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on confidentiality, integrity, availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 46 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 9.8 — CRITICAL (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **EPSS (FIRST):** 0.6% probability of exploitation in the next 30 days, higher than 49.2% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 6.9/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-09-14

## Is CVE-2026-78330 being exploited?

It currently carries a trending score of 41 in the Threadlinqs vulnerability feed.

## Affected products and versions

- [Apache Software Foundation](https://intel.threadlinqs.com/vendors/apache-software-foundation): Apache Syncope

## How to fix CVE-2026-78330

No vendor patch reference has been recorded for CVE-2026-78330 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-78330

1 tracked threat in the Threadlinqs corpus references CVE-2026-78330, either in the campaign’s CVE list or as an indicator on the campaign record.

- [September 2026 Microsoft Patch Tuesday — Record 966+ Vulnerabilities with Two Actively Exploited Zero-Days (CVE-2026-81963, CVE-2026-85880) and Multiple Critical Wormable RCEs](https://intel.threadlinqs.com/threat/TL-2026-2398) — CRITICAL · 2026-09-08

## Sources

Enriched from CVE.org, NVD, FIRST EPSS. Last verified by Threadlinqs on 2026-10-10. This product uses the NVD API but is not endorsed or certified by the NVD.

**Vendor advisory and patch**

- [lists.apache.org — vendor advisory](https://lists.apache.org/thread/vkqmmpwcdson285vtmzpbj9psw35hyo9)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-78330
Full detection coverage and IOCs for threats exploiting CVE-2026-78330 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp