How severe is CVE-2013-1762?

CVE-2013-1762 has a CVSS 2.0 base score of 6.6, rated medium severity.

Is CVE-2013-1762 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2013-1762?

CVE-2013-1762 primarily affects Stunnel. In total, 34 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2013-1762?

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

When was CVE-2013-1762 published?

CVE-2013-1762 was published on 2013-03-08 and last updated on 2026-06-16.

CVE-2013-1762

CVE-2013-1762 is a medium-severity vulnerability in Stunnel with a CVSS 2.0 base score of 6.6. 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-94.

Key facts

Severity: Medium (CVSS 2.0 base score 6.6)
EPSS exploit prediction: 3% (85th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-94
Affected product: Stunnel
Published: 2013-03-08
Last modified: 2026-06-16

Description

stunnel 4.21 through 4.54, when CONNECT protocol negotiation and NTLM authentication are enabled, does not correctly perform integer conversion, which allows remote proxy servers to execute arbitrary code via a crafted request that triggers a buffer overflow.

Frequently asked questions

What is CVE-2013-1762?: stunnel 4.21 through 4.54, when CONNECT protocol negotiation and NTLM authentication are enabled, does not correctly perform integer conversion, which allows remote proxy servers to execute arbitrary code via a crafted request that triggers a buffer overflow.
How severe is CVE-2013-1762?: CVE-2013-1762 has a CVSS 2.0 base score of 6.6, rated medium severity.
Is CVE-2013-1762 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2013-1762?: CVE-2013-1762 primarily affects Stunnel. In total, 34 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2013-1762?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2013-1762 published?: CVE-2013-1762 was published on 2013-03-08 and last updated on 2026-06-16.

References

Affected products (34)

cpe:2.3:a:stunnel:stunnel:*:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.21:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.22:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.23:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.24:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.25:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.26:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.27:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.28:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.29:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.30:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.31:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.32:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.33:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.34:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.35:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.36:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.37:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.38:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.39:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.40:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.41:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.42:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.43:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.44:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.45:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.46:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.47:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.48:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.49:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.50:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.51:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.52:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:4.53:*:*:*:*:*:*:*

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