How severe is CVE-2011-4006?

CVE-2011-4006 has a CVSS 2.0 base score of 7.8, rated high severity.

Is CVE-2011-4006 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-4006?

CVE-2011-4006 primarily affects Cisco Adaptive Security Appliance Software. In total, 26 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-4006?

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-2011-4006 published?

CVE-2011-4006 was published on 2012-05-02 and last updated on 2026-06-16.

CVE-2011-4006

CVE-2011-4006 is a high-severity vulnerability in Cisco Adaptive Security Appliance Software with a CVSS 2.0 base score of 7.8. 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: High (CVSS 2.0 base score 7.8)
EPSS exploit prediction: 1% (68th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Adaptive Security Appliance Software
Published: 2012-05-02
Last modified: 2026-06-16

Description

The ESMTP inspection feature on Cisco Adaptive Security Appliances (ASA) 5500 series devices with software 8.2 through 8.5 allows remote attackers to cause a denial of service (CPU consumption) via an unspecified closing sequence, aka Bug ID CSCtt32565.

Frequently asked questions

What is CVE-2011-4006?: The ESMTP inspection feature on Cisco Adaptive Security Appliances (ASA) 5500 series devices with software 8.2 through 8.5 allows remote attackers to cause a denial of service (CPU consumption) via an unspecified closing sequence, aka Bug ID CSCtt32565.
How severe is CVE-2011-4006?: CVE-2011-4006 has a CVSS 2.0 base score of 7.8, rated high severity.
Is CVE-2011-4006 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-4006?: CVE-2011-4006 primarily affects Cisco Adaptive Security Appliance Software. In total, 26 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-4006?: 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-2011-4006 published?: CVE-2011-4006 was published on 2012-05-02 and last updated on 2026-06-16.

References

Affected products (26)

cpe:2.3:o:cisco:adaptive_security_appliance_software:8.2\(1\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.2\(2\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.2\(3\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.2\(3.9\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.2\(4\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.2\(4.1\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.2\(4.4\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.2\(5\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.2.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.2.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.2.2:interim:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.2.3:*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.3\(1\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.3\(2\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.3.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.3.1:interim:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.3.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.4\(1\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.4\(1.11\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.4\(2\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.4\(2.11\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.5:*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.5\(1\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:8.5\(1.4\):*:*:*:*:*:*:*
cpe:2.3:h:cisco:5500_series_adaptive_security_appliance:*:*:*:*:*:*:*:*

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