Moodle Improper Encoding or Escaping of Output

published 2022-01-21 4 y ago modified 2026-09-08 2 mo ago also BIT-moodle-2021-40694 , EUVD-2022-6866 , GHSA-m37g-mwcg-7j7v

cvss: 4.9; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.9%; EPSS 0.9% chance of exploitation in 30 days, percentile 59%
public exploits: 0; none known

Insufficient escaping of the LaTeX preamble made it possible for site administrators to read files available to the HTTP server system account.

Patch / fix

fixed in 3

packagist moodle/moodle 3.9.10, 3.10.7, 3.11.3
bitnami moodle 3.9.10, 3.10.7, 3.11.3
moodle moodle 3.9.10, 3.10.7, 3.11.3

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2021-40694 updated 2025-11-21 cvss 7.5

moodle: arbitrary file read by site administrators via LaTeX preamble

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.90% chance of exploitation in the next 30 days, higher than 59% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
GitHub	3.1	4.9	CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N
NVD	3.1	4.9	CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N
OSV	3.1	4.9	CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N

Affected packages

ecosystem	package	affected	fixed in
packagist	moodle/moodle	>=3.9, <3.9.10 >=3.10, <3.10.7 >=3.11, <3.11.3	3.9.10 3.10.7 3.11.3
bitnami	moodle	<3.9.10 >=3.10.0, <3.10.7 >=3.11.0, <3.11.3	3.9.10 3.10.7 3.11.3

Affected products

n/a moodle

Classification

Weakness

CWE-116 Improper Encoding or Escaping of Output

References

bugzilla.redhat.com /show_bug.cgi?id=2043421
web, issue-tracking, third-party-advisory, advisory
nvd.nist.gov /vuln/detail/CVE-2021-40694
advisory, web
github.com /moodle/moodle
package

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary