Is CVE-2011-4586 being actively exploited?

CVE-2011-4586 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2011-4586?

CVE-2011-4586 has a CVSS 2.0 base score of 5.0 (MEDIUM).

CVE-2011-4586

MEDIUM · CVSS 5.0EPSS 2.1%EU EUVD

CRLF injection vulnerability in calendar/set.php in the Calendar subsystem in Moodle 1.9.x before 1.9.15, 2.0.x before 2.0.6, and 2.1.x before 2.1.3 allows remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks via unspecified vectors.

Key facts

CVSS score: 5.0 (v2.0)
Severity: MEDIUM
CVSS vector: AV:N/AC:L/Au:N/C:N/I:P/A:N
EPSS score: 2.1% (82th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2011-4511)
Published: July 20, 2012
NVD last modified: June 16, 2026
Status: Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2011-4511 in the EU Vulnerability Database. Last updated in EUVD on August 7, 2024.

View on the EU Vulnerability Database

Affected products

moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle
moodle / moodle

References

Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

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