CVE-2021-36395
CVE-2021-36395 is a high-severity vulnerability in Moodle with a CVSS 3.x base score of 7.5. 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-674.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- EPSS exploit prediction: 1% (50th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-674
- Affected product: Moodle
- Published:
- Last modified:
Description
In Moodle, the file repository's URL parsing required additional recursion handling to mitigate the risk of recursion denial of service.
Frequently asked questions
- What is CVE-2021-36395?
- In Moodle, the file repository's URL parsing required additional recursion handling to mitigate the risk of recursion denial of service.
- How severe is CVE-2021-36395?
- CVE-2021-36395 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2021-36395 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-36395?
- CVE-2021-36395 affects Moodle. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-36395?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2021-36395 published?
- CVE-2021-36395 was published on 2023-03-06 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:moodle:moodle:*:*:*:*:*:*:*:*
More vulnerabilities in Moodle
- CVE-2006-4935 — Critical (CVSS 10.0): The Database module in Moodle before 1.6.2 does not properly handle uploaded files, which has unspecified impact and…
- CVE-2006-4936 — Critical (CVSS 10.0): Moodle before 1.6.2 does not properly validate the module instance id when creating a course module object, which has…
- CVE-2005-2247 — Critical (CVSS 10.0): Multiple unknown vulnerabilities in Moodle before 1.5.1 have unknown impact and attack vectors.
- CVE-2004-2233 — Critical (CVSS 10.0): Unknown "front page vulnerability with Moodle servers" for Moodle before 1.3.2 has unknown impact and attack vectors.
- CVE-2004-2236 — Critical (CVSS 10.0): Unknown vulnerability in Moodle before 1.3.3 has unknown impact and attack vectors, related to language setting.
- CVE-2004-2237 — Critical (CVSS 10.0): Unknown vulnerability in Moodle before 1.3.4 has unknown impact and attack vectors, related to "strings in Moodle…
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