// For flags

CVE-2020-11501

gnutls: DTLS client hello contains a random value of all zeroes

Severity Score

7.4
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

GnuTLS 3.6.x before 3.6.13 uses incorrect cryptography for DTLS. The earliest affected version is 3.6.3 (2018-07-16) because of an error in a 2017-10-06 commit. The DTLS client always uses 32 '\0' bytes instead of a random value, and thus contributes no randomness to a DTLS negotiation. This breaks the security guarantees of the DTLS protocol.

GnuTLS versiones 3.6.x anteriores a 3.6.13, usa una criptografía incorrecta para DTLS. La primera versión afectada es 3.6.3 (16-07-2018) debido a un error en un commit del 06-10-2017. El cliente DTLS siempre usa 32 bytes "\0" en lugar de un valor aleatorio y, por lo tanto, no contribuye con la aleatoriedad en una negociación DTLS. Esto rompe las garantías de seguridad del protocolo DTLS.

A cryptographic weakness was found in the way DLTS implementation of GnuTLS, used zeros in place of random numbers. This flaw can break the security guarantee of the DTLS protocol.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None
Attack Vector
Network
Attack Complexity
Medium
Authentication
None
Confidentiality
Partial
Integrity
Partial
Availability
None
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2020-04-03 CVE Reserved
  • 2020-04-03 CVE Published
  • 2024-07-28 EPSS Updated
  • 2024-08-04 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-327: Use of a Broken or Risky Cryptographic Algorithm
  • CWE-330: Use of Insufficiently Random Values
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Gnu
Search vendor "Gnu"
 Gnutls
Search vendor "Gnu" for product "Gnutls"
 >= 3.6.3 < 3.6.13
Search vendor "Gnu" for product "Gnutls" and version " >= 3.6.3 < 3.6.13"
-
Affected
Canonical
Search vendor "Canonical"
 Ubuntu Linux
Search vendor "Canonical" for product "Ubuntu Linux"
 19.10
Search vendor "Canonical" for product "Ubuntu Linux" and version "19.10"
-
Affected
Debian
Search vendor "Debian"
 Debian Linux
Search vendor "Debian" for product "Debian Linux"
 10.0
Search vendor "Debian" for product "Debian Linux" and version "10.0"
-
Affected
Opensuse
Search vendor "Opensuse"
 Leap
Search vendor "Opensuse" for product "Leap"
 15.1
Search vendor "Opensuse" for product "Leap" and version "15.1"
-
Affected
Fedoraproject
Search vendor "Fedoraproject"
 Fedora
Search vendor "Fedoraproject" for product "Fedora"
 31
Search vendor "Fedoraproject" for product "Fedora" and version "31"
-
Affected
Fedoraproject
Search vendor "Fedoraproject"
 Fedora
Search vendor "Fedoraproject" for product "Fedora"
 32
Search vendor "Fedoraproject" for product "Fedora" and version "32"
-
Affected