How severe is CVE-2011-4582?

CVE-2011-4582 has a CVSS 2.0 base score of 4.9, rated medium severity.

Is CVE-2011-4582 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-2011-4582?

CVE-2011-4582 primarily affects Moodle. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-4582?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2011-4582 published?

CVE-2011-4582 was published on 2012-07-20 and last updated on 2026-06-16.

CVE-2011-4582

CVE-2011-4582 is a medium-severity vulnerability in Moodle with a CVSS 2.0 base score of 4.9. 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: Medium (CVSS 2.0 base score 4.9)
EPSS exploit prediction: 1% (64th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Moodle
Published: 2012-07-20
Last modified: 2026-06-16

Description

Open redirect vulnerability in the Calendar set page in Moodle 2.1.x before 2.1.3 allows remote authenticated users to redirect users to arbitrary web sites and conduct phishing attacks via a redirection URL.

Frequently asked questions

What is CVE-2011-4582?: Open redirect vulnerability in the Calendar set page in Moodle 2.1.x before 2.1.3 allows remote authenticated users to redirect users to arbitrary web sites and conduct phishing attacks via a redirection URL.
How severe is CVE-2011-4582?: CVE-2011-4582 has a CVSS 2.0 base score of 4.9, rated medium severity.
Is CVE-2011-4582 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-2011-4582?: CVE-2011-4582 primarily affects Moodle. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-4582?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2011-4582 published?: CVE-2011-4582 was published on 2012-07-20 and last updated on 2026-06-16.

References

Affected products (3)

cpe:2.3:a:moodle:moodle:2.1.0:*:*:*:*:*:*:*
cpe:2.3:a:moodle:moodle:2.1.1:*:*:*:*:*:*:*
cpe:2.3:a:moodle:moodle:2.1.2:*:*:*:*:*:*:*

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