CVE-2021-20280 Cross-site scripting (XSS) and Server side request forgery (SSRF) in moodle

What is CVE-2021-20280?

CVE-2021-20280 is a medium-severity cross-site scripting vulnerability in Fedoraproject Fedora, published on 15 Mar 2021. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

Official description

Text-based feedback answers required additional sanitizing to prevent stored XSS and blind SSRF risks in moodle before 3.10.2, 3.9.5, 3.8.8, 3.5.17.

Weakness: CWE-79

Which versions are affected by CVE-2021-20280?

9 open source packages ship an affected version, including moodle/moodle and moodle. It affects 2 products.

Products include Fedoraproject Fedora, Moodle Moodle.

How do I fix CVE-2021-20280?

Upgrade moodle/moodle to a fixed version for your release line: 3.10.2, 3.5.17, 3.8.8 or 3.9.5.

Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.

Is CVE-2021-20280 being exploited?

There is no known exploitation of CVE-2021-20280 in the wild and no public exploit code.

Other vulnerabilities in Fedoraproject Fedora

• CVE-2024-4577 PHP-CGI OS Command Injection Exploited Critical 9.8
• CVE-2021-39226 Grafana Authentication Bypass Exploited Critical 9.8
• CVE-2019-5544 VMware ESXi and Horizon DaaS OpenSLP Heap-Based Buffer Overflow Exploited Critical 9.8
• CVE-2024-4947 Google Chromium V8 Type Confusion Exploited Critical 9.6
• CVE-2024-4671 Google Chromium Visuals Use-After-Free Exploited Critical 9.6

All Fedoraproject Fedora vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BIT-moodle-2021-20280, GHSA-x2jp-hh65-4xvf, UBUNTU-CVE-2021-20280.