CVE-2021-36394
CVE-2021-36394 is a critical-severity vulnerability in Moodle with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-384.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- EPSS exploit prediction: 7% (93rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-384
- Affected product: Moodle
- Published:
- Last modified:
Description
In Moodle, a remote code execution risk was identified in the Shibboleth authentication plugin.
Frequently asked questions
- What is CVE-2021-36394?
- In Moodle, a remote code execution risk was identified in the Shibboleth authentication plugin.
- How severe is CVE-2021-36394?
- CVE-2021-36394 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-36394 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-36394?
- CVE-2021-36394 affects Moodle. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-36394?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2021-36394 published?
- CVE-2021-36394 was published on 2023-03-06 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:moodle:moodle:*:*:*:*:*:*:*:*
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