CVE-2025-67853
Published: 03 February 2026
Summary
CVE-2025-67853 is a high-severity Improper Restriction of Excessive Authentication Attempts (CWE-307) vulnerability in Moodle Moodle. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Brute Force (T1110); ranked at the 6.6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
Threat & Defense at a Glance
Threat & Defense Details
Likely Mitigating ControlsAI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
This control directly enforces limits on consecutive invalid logon attempts and automatic response (e.g., lockout) to prevent brute-force exploitation of authentication mechanisms.
Specific conditions can include excessive failed attempts, triggering stronger authentication that restricts brute-force exploitation.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Lack of rate limiting directly enables brute-force credential guessing (T1110) against the public-facing Moodle confirmation service (T1190).
NVD Description
A flaw was found in Moodle. A remote attacker could exploit a lack of proper rate limiting in the confirmation email service. This vulnerability allows attackers to more easily enumerate or guess user credentials, facilitating brute-force attacks against user accounts.
Deeper analysisAI
CVE-2025-67853 is a vulnerability in Moodle stemming from a lack of proper rate limiting in the confirmation email service. This flaw enables remote attackers to more easily enumerate or guess user credentials, thereby facilitating brute-force attacks against user accounts. The issue is classified under CWE-307 and carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N). It was published on 2026-02-03.
The vulnerability can be exploited by any remote attacker requiring no privileges, user interaction, or special conditions beyond network access. Attackers can leverage the absence of rate limiting to perform efficient credential guessing or enumeration via the confirmation email service, resulting in high confidentiality impact through unauthorized access to user accounts.
Red Hat provides details on mitigation in its security advisory at https://access.redhat.com/security/cve/CVE-2025-67853, with an associated Bugzilla entry at https://bugzilla.redhat.com/show_bug.cgi?id=2423847.
Details
- CWE(s)