Score 4.3 from GitHub Security Advisory published 2026-07-01. NVD baseline CVSS 4.3; sources differ by 0.0.
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
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.
July 1, 2026
July 6, 2026
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
Explore the affected products and dependency analysis for CVE-2026-53908
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