CVE-2023-28333 | Moodle: pix helper potential mustache code injection risk

The Mustache pix helper contained a potential Mustache injection risk if combined with user input (note: This did not appear to be implemented/exploitable anywhere in the core Moodle LMS).

Published: 2023-03-23 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-28333 is rated Moderate Risk (61.4/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 1.17%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-28333

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 1.06% 1.17% +0.10%
2 2026-04-29 0.85% 1.06% +0.21%
3 2026-04-27 — 0.85% —

Full EPSS history (23 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-28333

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2023-28333

GitHub Security Advisory for CVE-2023-28333

GHSA-q2x3-2f9g-h559 · Severity: critical · Ecosystem: composer — Moodle's Mustache pix helper contained a potential Mustache injection risk if combined with user input

OS Trackers for CVE-2023-28333

vendor priority summary link
ubuntu medium CVE-2023-28333 medium priority: Ubuntu including 1 source packages (moodle), 7 status rows across 7 suites (bionic, focal, jammy, kinetic, trusty, upstream, xenial): DNE 3, needs-triage 3, ignored 1. https://ubuntu.com/security/CVE-2023-28333

Affected software / configurations for CVE-2023-28333

Vendor Product Version Raw CPE
moodle moodle > 3.9.0, < 3.9.20 cpe:2.3:a:moodle:moodle:*:*:*:*:*:*:*:*
moodle moodle > 3.11.0, < 3.11.13 cpe:2.3:a:moodle:moodle:*:*:*:*:*:*:*:*
moodle moodle > 4.0.0, < 4.0.7 cpe:2.3:a:moodle:moodle:*:*:*:*:*:*:*:*
moodle moodle 3.9.0 cpe:2.3:a:moodle:moodle:3.9.0:-:*:*:*:*:*:*
moodle moodle 3.11.0 cpe:2.3:a:moodle:moodle:3.11.0:-:*:*:*:*:*:*
moodle moodle 4.0.0 cpe:2.3:a:moodle:moodle:4.0.0:-:*:*:*:*:*:*
moodle moodle 4.1.0 cpe:2.3:a:moodle:moodle:4.1.0:-:*:*:*:*:*:*
moodle moodle 4.1.1 cpe:2.3:a:moodle:moodle:4.1.1:*:*:*:*:*:*:*
fedoraproject fedora 36 cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*

References for CVE-2023-28333

cvelogic Threat Intelligence