How severe is CVE-2022-35653?

CVE-2022-35653 has a CVSS score of 6.1/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2022-35653?

CVE-2022-35653 affects the following packages: moodle/moodle (Packagist), moodle/moodle (Packagist), moodle/moodle (Packagist). Ecosystems affected: Packagist.

How do I fix CVE-2022-35653?

Update moodle/moodle to 4.0.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-35653 is resolved across your whole dependency graph.

How do I detect CVE-2022-35653 in my Packagist dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for moodle/moodle, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2022-35653 if there is no patch (or I can't update yet)?

Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Is CVE-2022-35653 actively exploited in the wild?

No public exploit code has been indexed for CVE-2022-35653 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2022-35653?

CVE-2022-35653 has an EPSS (Exploit Prediction Scoring System) score of 4.8%, placing it in the 92th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2022-35653?

CVE-2022-35653 is classified as Cross-site Scripting (XSS) (CWE-79). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

Is there exploit tooling available for CVE-2022-35653?

A Nuclei detection template exists for CVE-2022-35653, meaning automated scanners can fingerprint it. Public exploit tooling significantly increases real-world risk — prioritize patching and ensure detection coverage. Exploit tooling should only ever be used in isolated, authorized testing environments.

When was CVE-2022-35653 published, and has it been updated?

CVE-2022-35653 was published on July 25, 2022 and was last updated on October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CVE-2022-35653: moodle XSS

EPSS Exploitation Probability

via FIRST.org ↗

4.8%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs92th percentile — riskier than 92% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

3 pkgs affected

🐘moodle/moodle🐘moodle/moodle🐘moodle/moodle

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.

Description

A reflected XSS issue was identified in the LTI module of Moodle. The vulnerability exists due to insufficient sanitization of user-supplied data in the LTI module. 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 to steal potentially sensitive information, change appearance of the web page, can perform phishing and drive-by-download attacks. This vulnerability does not impact authenticated users.

Affected Packages

3 total 3 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`moodle/moodle`	≥ 4.0&&< 4.0.2	4.0.2`composer require moodle/moodle:^4.0.2`
🐘Packagist	`moodle/moodle`	≥ 3.11&&< 3.11.8	3.11.8`composer require moodle/moodle:^3.11.8`
🐘Packagist	`moodle/moodle`	≥ 3.9&&< 3.9.15	3.9.15`composer require moodle/moodle:^3.9.15`

Affected Products

3 products · 12 configurations

OS

fedorafedoraproject

2 versions

3536

Application

moodlemoodle

≥ 3.11.0 && < 3.11.8

2 versions

4.0.04.0.1

OS

enterprise linuxredhat

1 version

8.0

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for moodle/moodle, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update moodle/moodle to 4.0.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-35653 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

How to detect CVE-2022-35653

A community-maintained Nuclei template exists for this CVE. You can scan for it directly:

nuclei -id cve-2022-35653 -u https://target

Template: Moodle LTI module Reflected - Cross-Site Scripting
Severity: medium
Impact: Attackers can inject malicious JavaScript through the LTI module that executes in educators' or students' browsers, potentially stealing Moodle session credentials and accessing sensitive course information.
Remediation: Update Moodle to a patched version that properly sanitizes user input in the LTI module and prevents execution of injected scripts.

Template by ProjectDiscovery nuclei-templates (iamnoooob, pdresearch), MIT licensed. View the full template. Scan only systems you are authorised to test.

Frequently Asked Questions

A reflected XSS issue was identified in the LTI module of Moodle. The vulnerability exists due to insufficient sanitization of user-supplied data in the LTI module. 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 to steal potentially sensitive information, change appearance of the web page, can perform phishing and drive-by-download attacks. This vulnerability does not impact authenticated users.

O3 Security · Impact-Aware SCA

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CVE-2022-35653 — moodle

EPSS Exploitation Probability

How urgent is this, really

Where this sits among everything scored