CVE-2026-53902
MCO does not properly enforce authorization checks in the /customer/servlet/mco/webapi/profile-sections/group-membership endpoint. An authenticated user can modify their group membership without proper authorization checks, allowing privilege escalation. An attacker can add themselves to arbitrary groups by supplying a valid group ID, which can be obtained via other application functionalities (e.g. /customer/servlet/mco/webapi/group/picker/groups), provided he has necessary permissions, or potentially inferred through brute-force techniques.
Because vendor contact attempts were unsuccessful, the vulnerability has only been confirmed in version 25.3.3.1 but may also affect other versions.
- ⚠ NVD has not scored this CVE yet - manual triage required (common for recent CVEs)
Severity & exploitation scoring
AV:_/AC:_/... vector string published by NVD.ATT&CK techniques
1Techniques this CVE enables. Pills with a solid outline are high confidence - named directly in ATT&CK or Nuclei, or human-curated by CTID; the rest are inferred from the weakness type using MITRE's CVE Mapping Methodology and the CWE → CAPEC chain. Broad, generic-weakness guesses are filtered out. A small N× marks a technique that N independent sources agree on.
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