CVE-2026-76073
Received Received - Intake

Unauthorized Annotation Access in Label Studio

Publication date: 2026-08-24

Last updated on: 2026-08-24

Assigner: VulnCheck

Description
Label Studio does not scope the annotation detail endpoint to the requesting user's organization. AnnotationAPI in label_studio/tasks/api.py declares queryset = Annotation.objects.all() and provides no get_queryset override, so the default lookup retrieves any annotation by primary key. The view's permission_required entries name annotations.view, annotations.change and annotations.delete, and label_studio/core/permissions.py registers every permission with rules.is_authenticated, so the check is satisfied by any logged-in account and no object-level organization test runs. The sibling task endpoint does constrain its queryset with project__organization set to the requester's active organization, which is the boundary this path omits. Annotation identifiers are sequential integers, so an authenticated user of one organization can enumerate identifiers to read, modify and delete annotations belonging to other organizations on the same instance. The same unscoped queryset appears on AnnotationConvertAPI in the same file.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published
2026-08-24
Last Modified
2026-08-24
Generated
2026-08-24
AI Q&A
2026-08-24
EPSS Evaluated
N/A
NVD
CVE-2026-76073
EUVD
EUVD-2026-65060

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
humansignal label_studio 1.23.0

Helpful Resources

Exploitability

CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-639 The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.

Attack-Flow Graph

AI Quick Actions

Instant insights powered by AI
Executive Summary

This is an Insecure Direct Object Reference (IDOR) vulnerability in Label Studio's Annotation API endpoint. It allows authenticated users to read, modify, or delete annotations belonging to other organizations by exploiting sequential integer IDs. The issue occurs because the API uses an unfiltered queryset without enforcing organization-based access controls.

Detection Guidance

To detect this vulnerability, check if Label Studio version 1.23.0 or earlier is installed. Review API logs for unusual access patterns to the /api/annotations/{id}/ endpoint. Test by attempting to access annotations with sequential IDs across different organizations using authenticated requests.

Impact Analysis

An attacker in one organization can enumerate and manipulate annotations across all organizations. This could expose proprietary training data, corrupt model metrics, or cause irreversible data loss. The vulnerability affects Label Studio version 1.23.0 and exists in the file label_studio/tasks/api.py.

Compliance Impact

This vulnerability could lead to unauthorized access to sensitive data across organizations, violating GDPR's data protection principles and HIPAA's confidentiality requirements. Exposure of proprietary training data or model metrics may result in non-compliance with these regulations.

Mitigation Strategies

Upgrade Label Studio to a patched version beyond 1.23.0. Implement organization-based access controls in the AnnotationAPI by overriding get_queryset to filter annotations by the requester's organization. Restrict API access to trusted users and monitor for unauthorized annotation access attempts.

Chat Assistant

Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-76073. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70

EPSS Chart