5.4
MEDIUM CVSS 3.1
CVE-2026-102581
Moodle: xss in forum post templates due to insufficient escaping
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.

INFO

Published Date :

Sept. 30, 2026, 9:17 a.m.

Last Modified :

Oct. 1, 2026, 3:19 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-102581 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Moodle moodle
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 MEDIUM 92fb86c3-55a5-4fb5-9c3f-4757b9e96dc5
CVSS 3.1 MEDIUM [email protected]
CVSS 3.1 MEDIUM [email protected]
Solution
Apply Moodle updates to fix stored XSS in forum posts.
  • Update Moodle to the latest version.
  • Ensure template output is properly escaped.
  • Review forum post content for malicious scripts.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-102581.

URL Resource
http://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-88981 Patch
https://access.redhat.com/security/cve/CVE-2026-102581 Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2543634 Issue Tracking Third Party Advisory
https://moodle.org/mod/forum/discuss.php?d=482499 Vendor Advisory
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-102581 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-102581 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-102581 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-102581 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • Initial Analysis by [email protected]

    Oct. 01, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
    Added CPE Configuration OR *cpe:2.3:a:moodle:moodle:*:*:*:*:*:*:*:* versions up to (excluding) 4.5.13 *cpe:2.3:a:moodle:moodle:*:*:*:*:*:*:*:* versions from (including) 5.0.0 up to (excluding) 5.0.9 *cpe:2.3:a:moodle:moodle:*:*:*:*:*:*:*:* versions from (including) 5.1.0 up to (excluding) 5.1.6 *cpe:2.3:a:moodle:moodle:*:*:*:*:*:*:*:* versions from (including) 5.2.0 up to (excluding) 5.2.2
    Added Reference Type Fedora Project: http://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-88981 Types: Patch
    Added Reference Type Fedora Project: https://access.redhat.com/security/cve/CVE-2026-102581 Types: Third Party Advisory
    Added Reference Type Fedora Project: https://bugzilla.redhat.com/show_bug.cgi?id=2543634 Types: Issue Tracking, Third Party Advisory
    Added Reference Type Fedora Project: https://moodle.org/mod/forum/discuss.php?d=482499 Types: Vendor Advisory
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Sep. 30, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-102581', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-09-30T14:34:52.043531Z'}
  • New CVE Received by [email protected]

    Sep. 30, 2026

    Action Type Old Value New Value
    Added 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.
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
    Added CWE CWE-79
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/102xxx/CVE-2026-102581.json">CVE-2026-102581</a>
    Added Reference http://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-88981
    Added Reference https://access.redhat.com/security/cve/CVE-2026-102581
    Added Reference https://bugzilla.redhat.com/show_bug.cgi?id=2543634
    Added Reference https://moodle.org/mod/forum/discuss.php?d=482499
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.