How severe is CVE-2023-28333?

CVE-2023-28333 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-28333 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-28333?

CVE-2023-28333 primarily affects Moodle. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-28333?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2023-28333 published?

CVE-2023-28333 was published on 2023-03-23 and last updated on 2026-06-17.

CVE-2023-28333

CVE-2023-28333 is a critical-severity vulnerability in Moodle with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-94.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (64th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-94
Affected product: Moodle
Published: 2023-03-23
Last modified: 2026-06-17

Description

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).

Frequently asked questions

What is CVE-2023-28333?: 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).
How severe is CVE-2023-28333?: CVE-2023-28333 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-28333 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-28333?: CVE-2023-28333 primarily affects Moodle. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-28333?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2023-28333 published?: CVE-2023-28333 was published on 2023-03-23 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:a:moodle:moodle:*:*:*:*:*:*:*:*
cpe:2.3:a:moodle:moodle:3.9.0:-:*:*:*:*:*:*
cpe:2.3:a:moodle:moodle:3.11.0:-:*:*:*:*:*:*
cpe:2.3:a:moodle:moodle:4.0.0:-:*:*:*:*:*:*
cpe:2.3:a:moodle:moodle:4.1.0:-:*:*:*:*:*:*
cpe:2.3:a:moodle:moodle:4.1.1:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*

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