Medium severity · published Sep 30, 2026
CVE-2026-102581
Moodle: xss in forum post templates due to insufficient escaping
5.4
CVSS
0.2%
EPSS
No
On KEV
Description
A flaw was found in Moodle. Insufficient output escaping in templates used to display forum posts enables a stored cross-site scripting (XSS) vulnerability. An attacker can inject malicious content into a forum post, which then executes arbitrary script code in the browser of another user viewing the affected post.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 9% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MO
Moodle · Moodle
before 4.5.13; 5.0.0 before 5.0.9; 5.1.0 before 5.1.6; 5.2.0 before 5.2.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-102581
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-102581
git.moodle.org
http://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-88981
vdb-entry
https://access.redhat.com/security/cve/CVE-2026-102581
issue-tracking
https://bugzilla.redhat.com/show_bug.cgi?id=2543634
moodle.org
https://moodle.org/mod/forum/discuss.php?d=482499
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