How severe is CVE-2018-1137?

CVE-2018-1137 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.

Is CVE-2018-1137 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-1137?

CVE-2018-1137 affects Moodle. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-1137?

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-2018-1137 published?

CVE-2018-1137 was published on 2018-05-25 and last updated on 2026-06-17.

CVE-2018-1137

CVE-2018-1137 is a high-severity vulnerability in Moodle with a CVSS 3.x base score of 8.1. 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-20.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 5.5
EPSS exploit prediction: 2% (74th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Moodle
Published: 2018-05-25
Last modified: 2026-06-17

Description

An issue was discovered in Moodle 3.x. By substituting URLs in portfolios, users can instantiate any class. This can also be exploited by users who are logged in as guests to create a DDoS attack.

Frequently asked questions

What is CVE-2018-1137?: An issue was discovered in Moodle 3.x. By substituting URLs in portfolios, users can instantiate any class. This can also be exploited by users who are logged in as guests to create a DDoS attack.
How severe is CVE-2018-1137?: CVE-2018-1137 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.
Is CVE-2018-1137 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-1137?: CVE-2018-1137 affects Moodle. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-1137?: 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-2018-1137 published?: CVE-2018-1137 was published on 2018-05-25 and last updated on 2026-06-17.

References

Affected products (1)

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

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