XSS in Moodle
CVE-2021-20280
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.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.013 (68.9th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 69th percentile — 68.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.013 · newest: 0.013 · change: 0.000
Affected products
- Moodle
- Fedoraproject Fedora — versions 32, 33, 34
- Moodle — versions Fixed in 3.10.2, 3.9.5, 3.8.8, 3.5.17
Weakness classification (CWE)
Public proof-of-concept exploits
References
- bugzilla.redhat.com/show_bug.cgi (Third Party Advisory, Issue Tracking)
- moodle.org/mod/forum/discuss.php (Patch, Vendor Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- packetstormsecurity.com/files/164817/Moodle-Cross-Site-Scripting-Server-Side-Re… (Exploit, VDB Entry, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-20280?
- CVE-2021-20280 is a medium-severity vulnerability in Moodle, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2021-03-15.
- How severe is CVE-2021-20280?
- Medium severity. CVSS v3 base score is 5.4 out of 10.
- Is CVE-2021-20280 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.