Medium severity · published Feb 17, 2023
CVE-2023-23921
The vulnerability was found Moodle which exists due to insufficient sanitization of user-supplied data in some returnurl parameters
6.1
CVSS
0.8%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.8% · higher than 57% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MO
Moodle · Moodle
3.9.0 before 3.9.19; 3.11.0 before 3.11.12; 4.0.0 before 4.0.6; 4.1.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-23921
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-23921
Patch
http://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-76810
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=2162526
Patch
https://moodle.org/mod/forum/discuss.php?d=443272#p1782021
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