Moodle Link returnurl cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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4.7$0-$5k0.00

A vulnerability classified as problematic has been found in Moodle (Learning Management Software) (the affected version unknown). This affects an unknown part of the component Link Handler. The manipulation of the argument returnurl with an unknown input leads to a cross site scripting vulnerability. CWE is classifying the issue as CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. This is going to have an impact on integrity. The summary by CVE is:

The vulnerability was found Moodle which exists due to insufficient sanitization of user-supplied data in some returnurl parameters. A remote attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website. This flaw allows a remote attacker to perform cross-site scripting (XSS) attacks.

The weakness was disclosed 02/18/2023. It is possible to read the advisory at git.moodle.org. This vulnerability is uniquely identified as CVE-2023-23921 since 01/19/2023. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1059.007 according to MITRE ATT&CK.

Applying a patch is able to eliminate this problem. The bugfix is ready for download at git.moodle.org.

Productinfo

Type

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.7

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.1
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-74 / CWE-707
ATT&CK: T1059.007

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: Patch
Status: 🔍

0-Day Time: 🔍

Patch: git.moodle.org

Timelineinfo

01/19/2023 🔍
02/18/2023 +30 days 🔍
02/18/2023 +0 days 🔍
03/18/2023 +28 days 🔍

Sourcesinfo

Product: moodle.org

Advisory: git.moodle.org
Status: Confirmed

CVE: CVE-2023-23921 (🔍)

Entryinfo

Created: 02/18/2023 08:17
Updated: 03/18/2023 17:40
Changes: 02/18/2023 08:17 (40), 03/18/2023 17:40 (11)
Complete: 🔍

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