Description

Missing Authorization vulnerability in Apache Syncope. An administrator with task execution entitlements might be able to mass (de)provision group members, regardless of their group-related administration capabilities. 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.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "9.8",
  "pubDate": "2026-09-14T13:18:45.990Z",
  "pubdate": "2026-09-14T13:18:45.990Z",
  "executiveSummary": "A missing authorization vulnerability exists within Apache Syncope, classified as an Improper Authorization flaw.\nThe vulnerability allows an authenticated administrator possessing task execution entitlements to perform unauthorized group member de-provisioning or provisioning operations.\nThis bypass effectively circumvents established administrative boundary constraints, allowing actions outside the scope of the user's assigned group-related permissions.\nAffected products include Apache Syncope versions 3.0.0-M0 through 3.0.16, 4.0.0-M0 through 4.0.7, and 4.1.0-M0 through 4.1.2.\nThe risk implication is a significant escalation of privilege regarding identity lifecycle management, as an attacker with limited administrative scope can exert control over group memberships they are not authorized to manage.\nExploitation requires an existing administrative account with task execution privileges; no further unauthorized external access is strictly required, making this an internal privilege escalation threat.",
  "technicalDetails": "The root cause of this vulnerability lies in an insufficient authorization check during the execution of task-related workflows within the Apache Syncope architecture. Specifically, the system fails to perform a granular validation of the user's administrative entitlements against the scope of the target group when initiating provision or de-provision tasks.\nIn Apache Syncope, administrative capabilities are intended to be scoped according to the roles and realms assigned to a user. However, the task execution subsystem treats 'task execution' rights as an override or ignores the enforcement of realm-based and group-based administrative policies during the dispatch of these tasks.\nThe attack flow begins with an authenticated user who holds the necessary task execution permissions, but lacks specific administrative authority over a particular group. By triggering an administrative task—specifically those related to provisioning or de-provisioning—the user forces the backend execution engine to process the request without verifying if the user has the 'GROUP_UPDATE' or similar functional permissions for the specific target group subject.\nBecause the validation logic is missing at the task-execution layer, the system processes the request under a high-privilege context, ignoring the intended segregation of duties. This permits the attacker to manipulate group memberships (adding or removing members) for resources or groups that should be outside their organizational or administrative boundary.\nThe vulnerable component is the task management engine responsible for handling asynchronous or administrative provisioning workflows. The flaw persists across the identified versions because the authorization interceptors or service-layer guards do not adequately bridge the context of the user's restricted authorization claims with the execution requirements of the administrative tasks.\nSuccessful exploitation results in unauthorized identity lifecycle management, where an attacker can force the de-provisioning of users from critical groups or provision unauthorized entities into groups. This can lead to massive service disruption, loss of access control, or unauthorized privilege escalation for secondary accounts if group membership dictates system access levels.\nSince the vulnerability is triggered through established administrative interfaces, the network exposure is limited to the management port or interface where Syncope administrators interact with the console or REST API. No complex payload or memory corruption techniques are required, as the exploit relies entirely on legitimate API calls issued by an authorized, yet restricted, administrator."
}