Medium severity · published May 20, 2016
CVE-2016-3739
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…
5.3
CVSS
6.9%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)6.9% · higher than 94% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CU
Curl · Haxx
7.21.0; 7.21.1; 7.21.2; 7.21.3; 7.21.4; 7.21.5; +31 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2016-3739
CVE.org
https://www.cve.org/CVERecord?id=CVE-2016-3739
www.openwall.com
http://www.openwall.com/lists/oss-security/2024/03/27/4
www.oracle.com
http://www.oracle.com/technetwork/security-advisory/cpuoct2018-4428296.html
www.securityfocus.com
http://www.securityfocus.com/bid/90726
www.securitytracker.com
http://www.securitytracker.com/id/1035907
www.slackware.com
http://www.slackware.com/security/viewer.php?l=slackware-security&y=2016&m=slackware-security.495349
Vendor Advisory
https://curl.haxx.se/CVE-2016-3739.patch
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