How severe is CVE-2015-3644?

CVE-2015-3644 has a CVSS 2.0 base score of 5.8, rated medium severity.

Is CVE-2015-3644 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2015-3644?

CVE-2015-3644 primarily affects Stunnel. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2015-3644?

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

When was CVE-2015-3644 published?

CVE-2015-3644 was published on 2015-05-14 and last updated on 2026-06-17.

CVE-2015-3644

CVE-2015-3644 is a medium-severity vulnerability in Stunnel 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-284.

Key facts

Severity: Medium (CVSS 2.0 base score 5.8)
EPSS exploit prediction: 2% (80th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-284
Affected product: Stunnel
Published: 2015-05-14
Last modified: 2026-06-17

Description

Stunnel 5.00 through 5.13, when using the redirect option, does not redirect client connections to the expected server after the initial connection, which allows remote attackers to bypass authentication.

Frequently asked questions

What is CVE-2015-3644?: Stunnel 5.00 through 5.13, when using the redirect option, does not redirect client connections to the expected server after the initial connection, which allows remote attackers to bypass authentication.
How severe is CVE-2015-3644?: CVE-2015-3644 has a CVSS 2.0 base score of 5.8, rated medium severity.
Is CVE-2015-3644 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2015-3644?: CVE-2015-3644 primarily affects Stunnel. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2015-3644?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2015-3644 published?: CVE-2015-3644 was published on 2015-05-14 and last updated on 2026-06-17.

References

Affected products (14)

cpe:2.3:a:stunnel:stunnel:5.00:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:5.01:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:5.02:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:5.03:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:5.04:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:5.05:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:5.06:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:5.07:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:5.08:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:5.09:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:5.10:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:5.11:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:5.12:*:*:*:*:*:*:*
cpe:2.3:a:stunnel:stunnel:5.13:*:*:*:*:*:*:*

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