// For flags

CVE-2016-0701

OpenSSL Security Advisory 20171207

Severity Score

3.7
*CVSS v3

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

1
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

The DH_check_pub_key function in crypto/dh/dh_check.c in OpenSSL 1.0.2 before 1.0.2f does not ensure that prime numbers are appropriate for Diffie-Hellman (DH) key exchange, which makes it easier for remote attackers to discover a private DH exponent by making multiple handshakes with a peer that chose an inappropriate number, as demonstrated by a number in an X9.42 file.

La función DH_check_pub_key en crypto/dh/dh_check.c en OpenSSL 1.0.2 en versiones anteriores a 1.0.2f no asegura que los número primos son apropiados para el intercambio de clave Diffie-Hellman (DH), lo que hace que sea más fácil para atacantes remotos descubrir el exponente DH privado mediante la realización de múltiples apretones de mano con un par que eligió un número inapropiado, según lo demostrado por un número en un archivo X9.42.

There is a carry propagation bug in the MIPS32 and MIPS64 squaring procedure. Many EC algorithms are affected, including some of the TLS 1.3 default curves. Impact was not analyzed in detail, because the pre-requisites for attack are considered unlikely and include reusing private keys. Analysis suggests that attacks against RSA and DSA as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH are considered just feasible (although very difficult) because most of the work necessary to deduce information about a private key may be performed offline. The amount of resources required for such an attack would be significant. However, for an attack on TLS to be meaningful, the server would have to share the DH private key among multiple clients, which is no longer an option since CVE-2016-0701.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
None
Attack Vector
Network
Attack Complexity
High
Authentication
None
Confidentiality
Partial
Integrity
None
Availability
None
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2015-12-16 CVE Reserved
  • 2016-01-28 CVE Published
  • 2016-02-15 First Exploit
  • 2024-08-05 CVE Updated
  • 2025-04-01 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
CWE
  • CWE-200: Exposure of Sensitive Information to an Unauthorized Actor
CAPEC
References (25)
URL Date SRC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Openssl
Search vendor "Openssl"
Openssl
Search vendor "Openssl" for product "Openssl"
1.0.2
Search vendor "Openssl" for product "Openssl" and version "1.0.2"
-
Affected
Openssl
Search vendor "Openssl"
Openssl
Search vendor "Openssl" for product "Openssl"
1.0.2
Search vendor "Openssl" for product "Openssl" and version "1.0.2"
beta1
Affected
Openssl
Search vendor "Openssl"
Openssl
Search vendor "Openssl" for product "Openssl"
1.0.2
Search vendor "Openssl" for product "Openssl" and version "1.0.2"
beta2
Affected
Openssl
Search vendor "Openssl"
Openssl
Search vendor "Openssl" for product "Openssl"
1.0.2
Search vendor "Openssl" for product "Openssl" and version "1.0.2"
beta3
Affected
Openssl
Search vendor "Openssl"
Openssl
Search vendor "Openssl" for product "Openssl"
1.0.2a
Search vendor "Openssl" for product "Openssl" and version "1.0.2a"
-
Affected
Openssl
Search vendor "Openssl"
Openssl
Search vendor "Openssl" for product "Openssl"
1.0.2b
Search vendor "Openssl" for product "Openssl" and version "1.0.2b"
-
Affected
Openssl
Search vendor "Openssl"
Openssl
Search vendor "Openssl" for product "Openssl"
1.0.2c
Search vendor "Openssl" for product "Openssl" and version "1.0.2c"
-
Affected
Openssl
Search vendor "Openssl"
Openssl
Search vendor "Openssl" for product "Openssl"
1.0.2d
Search vendor "Openssl" for product "Openssl" and version "1.0.2d"
-
Affected
Openssl
Search vendor "Openssl"
Openssl
Search vendor "Openssl" for product "Openssl"
1.0.2e
Search vendor "Openssl" for product "Openssl" and version "1.0.2e"
-
Affected