How severe is CVE-2011-4318?

CVE-2011-4318 has a CVSS 2.0 base score of 5.8, rated medium severity.

Is CVE-2011-4318 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-4318?

CVE-2011-4318 primarily affects Dovecot. In total, 16 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-4318?

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

When was CVE-2011-4318 published?

CVE-2011-4318 was published on 2013-03-07 and last updated on 2026-06-16.

CVE-2011-4318

CVE-2011-4318 is a medium-severity vulnerability in Dovecot 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% (67th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Dovecot
Published: 2013-03-07
Last modified: 2026-06-16

Description

Dovecot 2.0.x before 2.0.16, when ssl or starttls is enabled and hostname is used to define the proxy destination, does not verify that the server hostname matches a domain name in the subject's Common Name (CN) of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via a valid certificate for a different hostname.

Frequently asked questions

What is CVE-2011-4318?: Dovecot 2.0.x before 2.0.16, when ssl or starttls is enabled and hostname is used to define the proxy destination, does not verify that the server hostname matches a domain name in the subject's Common Name (CN) of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via a valid certificate for a different hostname.
How severe is CVE-2011-4318?: CVE-2011-4318 has a CVSS 2.0 base score of 5.8, rated medium severity.
Is CVE-2011-4318 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-4318?: CVE-2011-4318 primarily affects Dovecot. In total, 16 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-4318?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2011-4318 published?: CVE-2011-4318 was published on 2013-03-07 and last updated on 2026-06-16.

References

Affected products (16)

cpe:2.3:a:dovecot:dovecot:2.0.0:*:*:*:*:*:*:*
cpe:2.3:a:dovecot:dovecot:2.0.1:*:*:*:*:*:*:*
cpe:2.3:a:dovecot:dovecot:2.0.2:*:*:*:*:*:*:*
cpe:2.3:a:dovecot:dovecot:2.0.3:*:*:*:*:*:*:*
cpe:2.3:a:dovecot:dovecot:2.0.4:*:*:*:*:*:*:*
cpe:2.3:a:dovecot:dovecot:2.0.5:*:*:*:*:*:*:*
cpe:2.3:a:dovecot:dovecot:2.0.6:*:*:*:*:*:*:*
cpe:2.3:a:dovecot:dovecot:2.0.7:*:*:*:*:*:*:*
cpe:2.3:a:dovecot:dovecot:2.0.8:*:*:*:*:*:*:*
cpe:2.3:a:dovecot:dovecot:2.0.9:*:*:*:*:*:*:*
cpe:2.3:a:dovecot:dovecot:2.0.10:*:*:*:*:*:*:*
cpe:2.3:a:dovecot:dovecot:2.0.11:*:*:*:*:*:*:*
cpe:2.3:a:dovecot:dovecot:2.0.12:*:*:*:*:*:*:*
cpe:2.3:a:dovecot:dovecot:2.0.13:*:*:*:*:*:*:*
cpe:2.3:a:dovecot:dovecot:2.0.14:*:*:*:*:*:*:*
cpe:2.3:a:dovecot:dovecot:2.0.15:*:*:*:*:*:*:*

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