Read the docs
TI-2016-03166 Aliases CVE-2016-3739GHSA-4rcg-2r46-4hcc

The (1) mbed_connect_step1 function in lib/vtls/mbedtls.c and (2) polarssl_connect_step1…

Priority LOW 34CWE-20Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
High
Impact type
—
Confidentiality · integrity · availability
None · High · None
Fix status
No fix listed

Attack profile from CVSS 3.0 · NVD. Fix status from CNA.

Summary

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.

Why it matters now

EPSS 0.06925 94th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 37

CPEVersionsRoleVendor
cpe:2.3:a:haxx:curl:7.21.0:*:*:*:*:*:*:*7.21.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.21.1:*:*:*:*:*:*:*7.21.1VulnerableHaxx
cpe:2.3:a:haxx:curl:7.21.2:*:*:*:*:*:*:*7.21.2VulnerableHaxx
cpe:2.3:a:haxx:curl:7.21.3:*:*:*:*:*:*:*7.21.3VulnerableHaxx
cpe:2.3:a:haxx:curl:7.21.4:*:*:*:*:*:*:*7.21.4VulnerableHaxx
cpe:2.3:a:haxx:curl:7.21.5:*:*:*:*:*:*:*7.21.5VulnerableHaxx
cpe:2.3:a:haxx:curl:7.21.6:*:*:*:*:*:*:*7.21.6VulnerableHaxx
cpe:2.3:a:haxx:curl:7.21.7:*:*:*:*:*:*:*7.21.7VulnerableHaxx
cpe:2.3:a:haxx:curl:7.22.0:*:*:*:*:*:*:*7.22.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.23.0:*:*:*:*:*:*:*7.23.0VulnerableHaxx
  • cpe:2.3:a:haxx:curl:7.21.0:*:*:*:*:*:*:* Versions 7.21.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.21.1:*:*:*:*:*:*:* Versions 7.21.1 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.21.2:*:*:*:*:*:*:* Versions 7.21.2 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.21.3:*:*:*:*:*:*:* Versions 7.21.3 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.21.4:*:*:*:*:*:*:* Versions 7.21.4 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.21.5:*:*:*:*:*:*:* Versions 7.21.5 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.21.6:*:*:*:*:*:*:* Versions 7.21.6 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.21.7:*:*:*:*:*:*:* Versions 7.21.7 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.22.0:*:*:*:*:*:*:* Versions 7.22.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.23.0:*:*:*:*:*:*:* Versions 7.23.0 Vulnerable ·Haxx
Show 27 more CPE
CPEVersionsRoleVendor
cpe:2.3:a:haxx:curl:7.23.1:*:*:*:*:*:*:*7.23.1VulnerableHaxx
cpe:2.3:a:haxx:curl:7.24.0:*:*:*:*:*:*:*7.24.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.25.0:*:*:*:*:*:*:*7.25.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.26.0:*:*:*:*:*:*:*7.26.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.27.0:*:*:*:*:*:*:*7.27.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.28.0:*:*:*:*:*:*:*7.28.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.28.1:*:*:*:*:*:*:*7.28.1VulnerableHaxx
cpe:2.3:a:haxx:curl:7.29.0:*:*:*:*:*:*:*7.29.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.30.0:*:*:*:*:*:*:*7.30.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.31.0:*:*:*:*:*:*:*7.31.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.32.0:*:*:*:*:*:*:*7.32.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.33.0:*:*:*:*:*:*:*7.33.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.34.0:*:*:*:*:*:*:*7.34.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.35.0:*:*:*:*:*:*:*7.35.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.36.0:*:*:*:*:*:*:*7.36.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.38.0:*:*:*:*:*:*:*7.38.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.39.0:*:*:*:*:*:*:*7.39.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.40.0:*:*:*:*:*:*:*7.40.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.41.0:*:*:*:*:*:*:*7.41.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.42.0:*:*:*:*:*:*:*7.42.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.42.1:*:*:*:*:*:*:*7.42.1VulnerableHaxx
cpe:2.3:a:haxx:curl:7.43.0:*:*:*:*:*:*:*7.43.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.44.0:*:*:*:*:*:*:*7.44.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.45.0:*:*:*:*:*:*:*7.45.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.46.0:*:*:*:*:*:*:*7.46.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.47.0:*:*:*:*:*:*:*7.47.0VulnerableHaxx
cpe:2.3:a:haxx:curl:7.48.0:*:*:*:*:*:*:*7.48.0VulnerableHaxx
  • cpe:2.3:a:haxx:curl:7.23.1:*:*:*:*:*:*:* Versions 7.23.1 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.24.0:*:*:*:*:*:*:* Versions 7.24.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.25.0:*:*:*:*:*:*:* Versions 7.25.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.26.0:*:*:*:*:*:*:* Versions 7.26.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.27.0:*:*:*:*:*:*:* Versions 7.27.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.28.0:*:*:*:*:*:*:* Versions 7.28.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.28.1:*:*:*:*:*:*:* Versions 7.28.1 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.29.0:*:*:*:*:*:*:* Versions 7.29.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.30.0:*:*:*:*:*:*:* Versions 7.30.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.31.0:*:*:*:*:*:*:* Versions 7.31.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.32.0:*:*:*:*:*:*:* Versions 7.32.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.33.0:*:*:*:*:*:*:* Versions 7.33.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.34.0:*:*:*:*:*:*:* Versions 7.34.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.35.0:*:*:*:*:*:*:* Versions 7.35.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.36.0:*:*:*:*:*:*:* Versions 7.36.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.38.0:*:*:*:*:*:*:* Versions 7.38.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.39.0:*:*:*:*:*:*:* Versions 7.39.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.40.0:*:*:*:*:*:*:* Versions 7.40.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.41.0:*:*:*:*:*:*:* Versions 7.41.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.42.0:*:*:*:*:*:*:* Versions 7.42.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.42.1:*:*:*:*:*:*:* Versions 7.42.1 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.43.0:*:*:*:*:*:*:* Versions 7.43.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.44.0:*:*:*:*:*:*:* Versions 7.44.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.45.0:*:*:*:*:*:*:* Versions 7.45.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.46.0:*:*:*:*:*:*:* Versions 7.46.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.47.0:*:*:*:*:*:*:* Versions 7.47.0 Vulnerable ·Haxx
  • cpe:2.3:a:haxx:curl:7.48.0:*:*:*:*:*:*:* Versions 7.48.0 Vulnerable ·Haxx

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

Not affected: 5 products
  • Red Hat Enterprise Linux 5
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Virtualization 3
  • Red Hat JBoss Enterprise Web Server 3

Timeline

  1. 2026-10-02 Threatist record created from CVE-2016-3739
  2. 2026-10-03 Alias added: GHSA-4rcg-2r46-4hcc

References

Advisory 4

Other 5

  • TI-2026-16162 Negotiate ambient user conn reuse CVSS 3.1CRITICAL 9.8
  • TI-2026-10231 cross-origin Digest auth state leak CVSS 3.1CRITICAL 9.8
  • TI-2026-09063 HTTP/2 stream-dependency tree UAF CVSS 3.1CRITICAL 9.8
  • TI-2026-07976 stale proxy password leak CVSS 3.1CRITICAL 9.8
  • TI-2026-07845 SASL double-free CVSS 3.1CRITICAL 9.8
  • TI-2023-12257 Injection in https://github.com/curl/curl CVSS 3.1CRITICAL 9.8
See all 168 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences