How severe is CVE-2011-5239?

CVE-2011-5239 has a CVSS 2.0 base score of 5.8, rated medium severity.

Is CVE-2011-5239 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-5239?

CVE-2011-5239 primarily affects Civicrm. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-5239?

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

When was CVE-2011-5239 published?

CVE-2011-5239 was published on 2012-11-06 and last updated on 2026-06-16.

CVE-2011-5239

CVE-2011-5239 is a medium-severity vulnerability in Civicrm with a CVSS 2.0 base score of 5.8. 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-20.

Key facts

Severity: Medium (CVSS 2.0 base score 5.8)
EPSS exploit prediction: 1% (41st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Civicrm
Published: 2012-11-06
Last modified: 2026-06-16

Description

CiviCRM 4.0.5 and 4.1.1 does not verify that the server hostname matches a domain name in the subject's Common Name (CN) or subjectAltName field of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via an arbitrary valid certificate.

Frequently asked questions

What is CVE-2011-5239?: CiviCRM 4.0.5 and 4.1.1 does not verify that the server hostname matches a domain name in the subject's Common Name (CN) or subjectAltName field of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via an arbitrary valid certificate.
How severe is CVE-2011-5239?: CVE-2011-5239 has a CVSS 2.0 base score of 5.8, rated medium severity.
Is CVE-2011-5239 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-5239?: CVE-2011-5239 primarily affects Civicrm. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-5239?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2011-5239 published?: CVE-2011-5239 was published on 2012-11-06 and last updated on 2026-06-16.

References

http://www.unrest.ca/peerjacking

Affected products (2)

cpe:2.3:a:civicrm:civicrm:4.0.5:*:*:*:*:*:*:*
cpe:2.3:a:civicrm:civicrm:4.1.1:*:*:*:*:*:*:*

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