What’s Vulnerable › Vulnerabilities
CVE-2021-20280
- Severity: medium (CVSS 5.4 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 1.3% probability of exploitation in the next 30 days
- Public exploit or detection template: yes
- Published: 2021-03-15 · updated 2026-06-17
- Weakness: CWE-79
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.
Affected products
- Fedoraproject Fedora: 32, 33, 34
- Moodle: from 3.5.0 before 3.5.17; from 3.8.0 before 3.8.8; from 3.9.0 before 3.9.5; from 3.10.0 before 3.10.2 — fixed in 3.10.2, 3.5.17, 3.8.8, 3.9.5
How to fix
Upgrade to a fixed version: Moodle 3.10.2, 3.5.17, 3.8.8, 3.9.5. Check the vendor advisory for mitigations.
References
- http://packetstormsecurity.com/files/164817/Moodle-Cross-Site-Scripting-Server-Side-Request-Forgery.html
- https://bugzilla.redhat.com/show_bug.cgi?id=1939037
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AFSNJ7XHVTC52RSRX2GBQFF3VEEAY2MS/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FGOMHMYM3WICJ6D6U22Z6LPJGT5A6MZM/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UFH5DDMU5TZ3JT4Q52WMRAHACA5MHIMT/
- https://moodle.org/mod/forum/discuss.php?d=419651
- http://packetstormsecurity.com/files/164817/Moodle-Cross-Site-Scripting-Server-Side-Request-Forgery.html
- https://bugzilla.redhat.com/show_bug.cgi?id=1939037
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AFSNJ7XHVTC52RSRX2GBQFF3VEEAY2MS/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FGOMHMYM3WICJ6D6U22Z6LPJGT5A6MZM/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UFH5DDMU5TZ3JT4Q52WMRAHACA5MHIMT/
- https://moodle.org/mod/forum/discuss.php?d=419651
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