CVE-2021-20280

lowpriority · track · 22EPSS 0.013 · 70 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.27% (70th) EPSS

CVSS 3.5 · low

Is it mine?

16 products

Who says so?

4 sources

cnnvd · enisa_euvd · osv · nvd

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

5.4

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 3.5–5.4

v2.03.5lowAV:N/AC:M/Au:S/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 6.8 · impact 2.9

v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:Nprimary · NVD / NIST USexploitability 2.3 · impact 2.7

v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:Nsecondary · OSV

v3.15mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)

The CWE weakness classes this flaw belongs to.

Products and version ranges known to be affected.

Vendor and ecosystem advisories describing this.

GHSA-x2jp-hh65-4xvfCross-site scripting (XSS) and Server side request forgery (SSRF) in moodle2021-03-29ghsa · osvUS
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.
BIT-moodle-2021-202802024-03-06vendor · osvUS
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.

Other names and identifiers for this entity.

Which sources assert this record, and when.

published 2021-03-15modified 2026-06-17

External citations — patches, advisories, analysis.

scry

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