CVE-2025-53021
MEDIUM EPSS 17.4%
Published Jun 24, 20251y ago · Modified Jun 17, 20261w ago
4.2 CVSS 3.1
Published Jun 24, 2025 1y ago
Last Modified Jun 17, 2026 1w ago
Description
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 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.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N Attack Vector Network
Attack Complexity High
Privileges Required None
User Interaction Required
Scope Unchanged
Confidentiality Low
Integrity Low
Availability None
Threat Intelligence
EPSS Exploit Probability
17.4% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available
Weaknesses 1
CWE-384
Affected Products 1
| Vendor | Product | Version | Range |
|---|---|---|---|
| moodle | moodle | * | ≥3.0.0 – ≤3.11.18 |
References 3
- github.com https://github.com/moodle/moodle/releases/tag/v3.11.18
- moodledev.io https://moodledev.io/general/releases#moodle-311
- rentry.co https://rentry.co/moodle-oauth2-cve
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.