CVE-2021-36400
CVE-2021-36400 is a medium-severity vulnerability in Moodle with a CVSS 3.x base score of 5.3. 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-639.
Key facts
- Severity: Medium (CVSS 3.x base score 5.3)
- EPSS exploit prediction: 1% (40th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-639
- Affected product: Moodle
- Published:
- Last modified:
Description
In Moodle, insufficient capability checks made it possible to remove other users' calendar URL subscriptions.
Frequently asked questions
- What is CVE-2021-36400?
- In Moodle, insufficient capability checks made it possible to remove other users' calendar URL subscriptions.
- How severe is CVE-2021-36400?
- CVE-2021-36400 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
- Is CVE-2021-36400 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-36400?
- CVE-2021-36400 affects Moodle. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-36400?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-36400 published?
- CVE-2021-36400 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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