CVE-2026-53908 (GCVE-0-2026-53908)
Vulnerability from cvelistv5 – Published: 2026-07-01 11:59 – Updated: 2026-07-01 13:38
VLAI
Title
User Enumeration in MCO
Summary
MCO is vulnerable to User Enumeration through authentication-related functionalities. The application returns distinguishable responses for valid and invalid users during username reminder and password reset operations. An attacker can leverage these differences to enumerate valid usernames and email addresses.
Because vendor contact attempts were unsuccessful, the vulnerability has only been confirmed in version 25.3.3.1 but may also affect other versions.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-204 - Observable Response Discrepancy
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://cert.pl/en/posts/2026/07/CVE-2026-53902 | third-party-advisory |
| https://mco.mycomplianceoffice.com/ | product |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| MyComplianceOffice | MCO |
Affected:
25.3.3.1
(custom)
|
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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