stunnel: authentication bypass with the "redirect" option
Published May 14, 2015
5.8
MEDIUMCVSS 2.0
EPSS 2.12%
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.
Affected products
No data.
- 5.00
- 5.01
- 5.02
- 5.03
- 5.04
- 5.05
- 5.06
- 5.07
- 5.08
- 5.09
- 5.10
- 5.11
- 5.12
- 5.13
No data.
Red Hat Enterprise Linux 5
stunnel
Not affected
Red Hat Enterprise Linux 6
stunnel
Not affected
Red Hat Enterprise Linux 7
stunnel
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | stunnel | Not affected | n/a |
| Red Hat Enterprise Linux 6 | stunnel | Not affected | n/a |
| Red Hat Enterprise Linux 7 | stunnel | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
Not vulnerable. This issue did not affect the versions of stunnel as shipped with Red Hat Enterprise Linux 5, 6, and 7.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
No CVSS v3.0 score for this CVE.
AV:N/AC:M/Au:N/C:P/I:P/A:N
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 4, 2026.
Score over time
2022-2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (10 key points)
Flat stretches are collapsed. Showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 4, 2026 | 2.12% (0.02120) | 81.23th | v5 (v2026.06.15) |
| Jun 15, 2026 | 2.14% (0.02136) | 79.56th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.16% (0.00156) | 33.88th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.41% (0.00410) | 74.70th | v3 (v2023.03.01) |
| Feb 8, 2024 | 0.41% (0.00410) | 73.19th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.41% (0.00410) | 69.81th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.21% (0.01213) | 66.61th | v2 (v2022.01.01) |
| Feb 17, 2023 | 1.21% (0.01213) | 66.22th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.21% (0.01213) | 64.21th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.21% (0.01213) | 40.54th | v2 (v2022.01.01) |
References (8)
- http://www.debian.org/security/2015/dsa-3299 vendor-advisoryx_refsource_DEBIAN
- http://www.securityfocus.com/bid/74659 vdb-entryx_refsource_BID
- http://www.securitytracker.com/id/1032324 vdb-entryx_refsource_SECTRACK
- https://access.redhat.com/security/cve/CVE-2015-3644 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1221673 Issue Tracking
- https://nvd.nist.gov/vuln/detail/CVE-2015-3644
- https://www.cve.org/CVERecord?id=CVE-2015-3644
- https://www.stunnel.org/CVE-2015-3644.html x_refsource_CONFIRMPatchVendor Advisory
| Link | Providers | Tags |
|---|---|---|
| http://www.debian.org/security/2015/dsa-3299 | vendor-advisoryx_refsource_DEBIAN | |
| http://www.securityfocus.com/bid/74659 | vdb-entryx_refsource_BID | |
| http://www.securitytracker.com/id/1032324 | vdb-entryx_refsource_SECTRACK | |
| https://access.redhat.com/security/cve/CVE-2015-3644 | Vendor Advisory | |
| https://bugzilla.redhat.com/show_bug.cgi?id=1221673 | Issue Tracking | |
| https://nvd.nist.gov/vuln/detail/CVE-2015-3644 | ||
| https://www.cve.org/CVERecord?id=CVE-2015-3644 | ||
| https://www.stunnel.org/CVE-2015-3644.html | x_refsource_CONFIRMPatchVendor Advisory |
Change history (0)
No recorded changes yet.