How severe is CVE-2011-2940?

CVE-2011-2940 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2011-2940 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-2940?

CVE-2011-2940 primarily affects Stunnel. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-2940?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2011-2940 published?

CVE-2011-2940 was published on 2011-08-25 and last updated on 2026-06-16.

CVE-2011-2940

CVE-2011-2940 is a critical-severity vulnerability in Stunnel with a CVSS 2.0 base score of 9.3. 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-119.

Key facts

Severity: Critical (CVSS 2.0 base score 9.3)
EPSS exploit prediction: 6% (92nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-119
Affected product: Stunnel
Published: 2011-08-25
Last modified: 2026-06-16

Description

stunnel 4.40 and 4.41 might allow remote attackers to execute arbitrary code or cause a denial of service (heap memory corruption) via unspecified vectors.

Frequently asked questions

What is CVE-2011-2940?: stunnel 4.40 and 4.41 might allow remote attackers to execute arbitrary code or cause a denial of service (heap memory corruption) via unspecified vectors.
How severe is CVE-2011-2940?: CVE-2011-2940 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2011-2940 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-2940?: CVE-2011-2940 primarily affects Stunnel. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-2940?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2011-2940 published?: CVE-2011-2940 was published on 2011-08-25 and last updated on 2026-06-16.

References

Affected products (2)

cpe:2.3:a:stunnel:stunnel:4.40:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.41:*:*:*:*:*:*:*

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