CVE-2025-53021
Published: 24 June 2025
Summary
CVE-2025-53021 is a medium-severity Session Fixation (CWE-384) vulnerability in Moodle Moodle. Its CVSS base score is 4.2 (Medium).
Operationally, ranked in the top 34.2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-19060
Vulnerability details
A session fixation vulnerability in Moodle 3.x through 3.11.18 allows unauthenticated attackers to hijack user sessions via the sesskey parameter. The sesskey can be obtained without authentication and reused within the OAuth2 login flow, resulting in the victim's session being…
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linked to the attacker's. Successful exploitation results in full account takeover. According to the Moodle Releases page, "Bug fixes for security issues in 3.11.x ended 11 December 2023." NOTE: This vulnerability only affects products that are no longer supported by the maintainer.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
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.
Session termination after a set interval shortens the usable lifetime of a fixed session identifier, making successful exploitation of session fixation more difficult.
Re-authentication typically forces issuance of a new session, limiting the window for exploitation of a previously fixed session identifier.
Enforces proper session ID generation and binding, preventing fixation of a known session token.