curl: TLS certificate name check bypass with mbedTLS and PolarSSL
Published May 20, 2016
5.3
MEDIUMCVSS 3.0
EPSS 6.93%
Description
The (1) mbed_connect_step1 function in lib/vtls/mbedtls.c and (2) polarssl_connect_step1 function in lib/vtls/polarssl.c in cURL and libcurl before 7.49.0, when using SSLv3 or making a TLS connection to a URL that uses a numerical IP address, allow remote attackers to spoof servers via an arbitrary valid certificate.
Affected products
No data.
- 7.21.0
- 7.21.1
- 7.21.2
- 7.21.3
- 7.21.4
- 7.21.5
- 7.21.6
- 7.21.7
- 7.22.0
- 7.23.0
- 7.23.1
- 7.24.0
- 7.25.0
- 7.26.0
- 7.27.0
- 7.28.0
- 7.28.1
- 7.29.0
- 7.30.0
- 7.31.0
- 7.32.0
- 7.33.0
- 7.34.0
- 7.35.0
- 7.36.0
- 7.38.0
- 7.39.0
- 7.40.0
- 7.41.0
- 7.42.0
- 7.42.1
- 7.43.0
- 7.44.0
- 7.45.0
- 7.46.0
- 7.47.0
- 7.48.0
No data.
Red Hat Enterprise Linux 5
curl
Not affected
Red Hat Enterprise Linux 6
curl
Not affected
Red Hat Enterprise Linux 7
curl
Not affected
Red Hat Enterprise Virtualization 3
mingw-virt-viewer
Not affected
Red Hat JBoss Enterprise Web Server 3
curl
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | curl | Not affected | n/a |
| Red Hat Enterprise Linux 6 | curl | Not affected | n/a |
| Red Hat Enterprise Linux 7 | curl | Not affected | n/a |
| Red Hat Enterprise Virtualization 3 | mingw-virt-viewer | Not affected | n/a |
| Red Hat JBoss Enterprise Web Server 3 | curl | Not affected | n/a |
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N
AV:N/AC:H/Au:N/C:N/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 1, 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 (34 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 6.93% (0.06925) | 93.90th | v5 (v2026.06.15) |
| Jun 15, 2026 | 6.38% (0.06377) | 92.75th | v5 (v2026.06.15) |
| Mar 4, 2026 | 1.07% (0.01068) | 77.40th | v4 (v2025.03.14) |
| Mar 1, 2026 | 2.18% (0.02178) | 84.12th | v4 (v2025.03.14) |
| Feb 4, 2026 | 1.07% (0.01068) | 77.30th | v4 (v2025.03.14) |
| Feb 1, 2026 | 2.18% (0.02178) | 84.03th | v4 (v2025.03.14) |
| Jan 4, 2026 | 1.07% (0.01068) | 77.22th | v4 (v2025.03.14) |
| Jan 1, 2026 | 2.18% (0.02178) | 83.96th | v4 (v2025.03.14) |
| Dec 4, 2025 | 1.07% (0.01068) | 77.05th | v4 (v2025.03.14) |
| Dec 1, 2025 | 2.18% (0.02178) | 83.87th | v4 (v2025.03.14) |
| Nov 4, 2025 | 1.07% (0.01068) | 77.00th | v4 (v2025.03.14) |
| Nov 1, 2025 | 2.18% (0.02178) | 83.84th | v4 (v2025.03.14) |
| Oct 4, 2025 | 1.07% (0.01068) | 76.97th | v4 (v2025.03.14) |
| Oct 1, 2025 | 2.18% (0.02178) | 83.80th | v4 (v2025.03.14) |
| Sep 4, 2025 | 1.07% (0.01068) | 76.89th | v4 (v2025.03.14) |
| Sep 1, 2025 | 2.18% (0.02178) | 83.77th | v4 (v2025.03.14) |
| Aug 4, 2025 | 1.08% (0.01083) | 76.94th | v4 (v2025.03.14) |
| Aug 1, 2025 | 2.23% (0.02225) | 83.93th | v4 (v2025.03.14) |
| Jul 4, 2025 | 1.08% (0.01083) | 76.89th | v4 (v2025.03.14) |
| Jul 1, 2025 | 2.23% (0.02225) | 83.85th | v4 (v2025.03.14) |
| Jun 4, 2025 | 1.08% (0.01083) | 76.80th | v4 (v2025.03.14) |
| Jun 1, 2025 | 2.23% (0.02225) | 83.75th | v4 (v2025.03.14) |
| May 7, 2025 | 1.08% (0.01083) | 76.65th | v4 (v2025.03.14) |
| May 4, 2025 | 2.82% (0.02818) | 85.36th | v4 (v2025.03.14) |
| May 1, 2025 | 5.84% (0.05838) | 90.06th | v4 (v2025.03.14) |
| Mar 30, 2025 | 2.82% (0.02818) | 84.89th | v4 (v2025.03.14) |
| Mar 29, 2025 | 5.80% (0.05799) | 83.75th | v4 (v2025.03.14) |
| Mar 17, 2025 | 2.82% (0.02818) | 85.22th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.75% (0.00754) | 81.71th | v3 (v2023.03.01) |
| Feb 8, 2024 | 0.75% (0.00754) | 80.44th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.75% (0.00754) | 78.13th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.96% (0.01955) | 78.47th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.96% (0.01955) | 76.59th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.96% (0.01955) | 55.71th | v2 (v2022.01.01) |
References (15)
- http://www.openwall.com/lists/oss-security/2024/03/27/4 mailing-list
- http://www.oracle.com/technetwork/security-advisory/cpuoct2018-4428296.html
- http://www.securityfocus.com/bid/90726 vdb-entry
- http://www.securitytracker.com/id/1035907 vdb-entry
- http://www.slackware.com/security/viewer.php?l=slackware-security&y=2016&m=slackware-security.495349 vendor-advisory
- https://access.redhat.com/security/cve/CVE-2016-3739 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1335430 Issue Tracking
- https://curl.haxx.se/CVE-2016-3739.patch Vendor Advisory
- https://curl.haxx.se/changes.html#7_49_0
- https://curl.haxx.se/docs/adv_20160518.html Vendor Advisory
- https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05320149
- https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05390722
- https://nvd.nist.gov/vuln/detail/CVE-2016-3739
- https://security.gentoo.org/glsa/201701-47 vendor-advisory
- https://www.cve.org/CVERecord?id=CVE-2016-3739
Change history (0)
No recorded changes yet.