Moodle File Repository URL Parser resource consumption

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
5.5$0-$5k0.00

Summaryinfo

A vulnerability described as problematic has been identified in Moodle. The impacted element is an unknown function of the component File Repository URL Parser. Such manipulation leads to resource consumption. This vulnerability is documented as CVE-2021-36395. There is not any exploit available.

Detailsinfo

A vulnerability was found in Moodle (Learning Management Software) (unknown version). It has been rated as problematic. Affected by this issue is an unknown code block of the component File Repository URL Parser. The manipulation with an unknown input leads to a resource consumption vulnerability. Using CWE to declare the problem leads to CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. Impacted is availability. CVE summarizes:

In Moodle, the file repository's URL parsing required additional recursion handling to mitigate the risk of recursion denial of service.

The weakness was released 03/07/2023. The advisory is shared for download at moodle.org. This vulnerability is handled as CVE-2021-36395 since 07/12/2021. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 07/05/2025).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2023-0827). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.5

VulDB Base Score: 3.5
VulDB Temp Score: 3.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Resource consumption
CWE: CWE-400 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

07/12/2021 🔍
03/07/2023 +603 days 🔍
03/07/2023 +0 days 🔍
07/05/2025 +851 days 🔍

Sourcesinfo

Product: moodle.org

Advisory: moodle.org
Status: Confirmed

CVE: CVE-2021-36395 (🔍)
GCVE (CVE): GCVE-0-2021-36395
GCVE (VulDB): GCVE-100-222416
EUVD: 🔍

Entryinfo

Created: 03/07/2023 08:11
Updated: 07/05/2025 21:46
Changes: 03/07/2023 08:11 (37), 04/01/2023 00:55 (11), 07/05/2025 21:46 (16)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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