CVE-2026-32821: dataCycle-CORE Auth Bypass Vulnerability

CVE-2026-32821 Overview

CVE-2026-32821 is a broken authorization vulnerability [CWE-285] in dataCycle-CORE, a data management system used for centrally storing, managing, searching, and distributing data. The flaw exists in the collection API controller, which evaluates permissions based on a user-supplied user_email parameter. Any authenticated API user holding a valid access token can request permission evaluation as another user. If the impersonated user owns collections, those collections become accessible through the API. Version 4 additionally exposes add_item and remove_item routes without object-level authorize! checks, enabling cross-user modification of collection contents.

Critical Impact
An authenticated attacker can access and modify other users' collections through the dataCycle-CORE API by supplying a target user_email, bypassing object-level authorization.

Affected Products

dataCycle-CORE versions up to and including 25.07.3
dataCycle-CORE V4 (affected by additional add_item/remove_item authorization bypass)
Fixed in dataCycle-CORE version 26.06.08

Discovery Timeline

2026-07-20 - CVE-2026-32821 published to NVD
2026-07-21 - Last updated in NVD database

Technical Details for CVE-2026-32821

Vulnerability Analysis

The vulnerability resides in the dataCycle-CORE collection API controller. The controller accepts a user_email parameter from authenticated API clients and uses that value to evaluate collection permissions. Rather than restricting the permission context to the caller's own identity, the controller trusts the client-provided email and returns collections belonging to the referenced user.

In dataCycle-CORE V4, the same controller exposes add_item and remove_item routes that operate on a known collection ID. These routes omit object-level authorize! calls, so any authenticated caller who can enumerate or guess a collection ID can add or remove items belonging to other users. The combination of read exposure via user_email and write exposure via missing object checks produces a cross-user modification path.

Root Cause

The root cause is improper authorization [CWE-285]. The controller conflates authentication with authorization by treating a valid access token as sufficient to act on behalf of an arbitrary user identified in a request parameter. Object-level authorization checks are missing on collection mutation endpoints in V4.

Attack Vector

Exploitation requires network access to the dataCycle-CORE API and any authenticated user account with a valid access token. The attacker sends a request to the collection API with the user_email parameter set to a target user. The API returns the target's collections. Once a collection ID is known, the attacker can invoke add_item or remove_item in V4 without triggering authorization enforcement.

For technical specifics, see the GitHub Security Advisory GHSA-vjjr-9q8g-mgx7.

Detection Methods for CVE-2026-32821

Indicators of Compromise

API requests to the collection endpoint containing a user_email parameter that does not match the authenticated caller's identity.
Access log entries showing a single access token retrieving collections associated with multiple distinct user identities.
Calls to add_item or remove_item routes originating from users who do not own the referenced collection ID.

Detection Strategies

Correlate authenticated user identity from access tokens against the user_email parameter submitted to collection API endpoints, and alert on mismatches.
Audit application logs for unexpected collection enumeration patterns, particularly bursts of requests iterating over user identifiers.
Review V4 mutation route access to identify item additions or removals not preceded by a legitimate ownership check.

Monitoring Recommendations

Enable verbose API request logging including caller identity, user_email values, and target collection IDs.
Forward dataCycle-CORE application logs to a centralized SIEM or data lake to support cross-user access analytics.
Track anomalous spikes in collection reads or item modifications per token as a leading indicator of abuse.

How to Mitigate CVE-2026-32821

Immediate Actions Required

Upgrade dataCycle-CORE to version 26.06.08 or later, which contains the vendor patch.
Rotate API access tokens after upgrading to invalidate any credentials that may have been misused.
Review historical API logs for evidence of cross-user access via the user_email parameter.

Patch Information

The issue is patched in dataCycle-CORE version 26.06.08. The fix is documented in the GitHub Security Advisory GHSA-vjjr-9q8g-mgx7. Administrators should apply the upgrade rather than rely on workarounds.

Workarounds

Restrict API access to trusted internal networks or specific IP allowlists until the patch is applied.
Revoke access tokens for non-essential users to reduce the population of accounts that can invoke the vulnerable endpoint.
Deploy an API gateway or reverse proxy rule that rejects requests containing a user_email parameter on the collection endpoint.

bash

# Example NGINX rule to block user_email parameter on collection API
location /api/v4/collections {
    if ($arg_user_email) {
        return 403;
    }
    proxy_pass http://datacycle_backend;
}