How severe is CVE-2023-35133?

CVE-2023-35133 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2023-35133 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-35133?

CVE-2023-35133 primarily affects Moodle. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-35133?

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

When was CVE-2023-35133 published?

CVE-2023-35133 was published on 2023-06-22 and last updated on 2026-06-17.

CVE-2023-35133

CVE-2023-35133 is a high-severity vulnerability in Moodle with a CVSS 3.x base score of 7.5. 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-918.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (53rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-918
Affected product: Moodle
Published: 2023-06-22
Last modified: 2026-06-17

Description

An issue in the logic used to check 0.0.0.0 against the cURL blocked hosts lists resulted in an SSRF risk. This flaw affects Moodle versions 4.2, 4.1 to 4.1.3, 4.0 to 4.0.8, 3.11 to 3.11.14, 3.9 to 3.9.21 and earlier unsupported versions.

Frequently asked questions

What is CVE-2023-35133?: An issue in the logic used to check 0.0.0.0 against the cURL blocked hosts lists resulted in an SSRF risk. This flaw affects Moodle versions 4.2, 4.1 to 4.1.3, 4.0 to 4.0.8, 3.11 to 3.11.14, 3.9 to 3.9.21 and earlier unsupported versions.
How severe is CVE-2023-35133?: CVE-2023-35133 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2023-35133 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-35133?: CVE-2023-35133 primarily affects Moodle. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-35133?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2023-35133 published?: CVE-2023-35133 was published on 2023-06-22 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:moodle:moodle:*:*:*:*:*:*:*:*
cpe:2.3:a:moodle:moodle:4.2.0:*:*:*:*:*:*:*

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