SSL/TLS Services Support RC4 (PCI DSS)

Medium Nessus Plugin ID 106458

Synopsis

A service on the remote host supports RC4

Description

At least one of the SSL or TLS services on the remote host supports the use of RC4 for encryption.

RC4 does not meet the PCI definition of strong cryptography as defined by NIST Special Publication 800-57 Part 1.

The RC4 cipher is flawed in its generation of a pseudo-random stream of bytes so that a wide variety of small biases are introduced into the stream, decreasing its randomness. If plaintext is repeatedly encrypted (e.g., HTTP cookies), and an attacker is able to obtain many (i.e., tens of millions) ciphertexts, the attacker may be able to derive the plaintext.

Solution

Consult the software's manual and reconfigure the service to disable support for RC4.

See Also

https://www.rc4nomore.com

https://blog.pcisecuritystandards.org/migrating-from-ssl-and-early-tls

Plugin Details

Severity: Medium

ID: 106458

File Name: pci_rc4_supported.nasl

Version: 1.3

Type: remote

Family: General

Published: 2018/01/29

Modified: 2018/07/24

Dependencies: 65821

Risk Information

Risk Factor: Medium

CVSSv2

Base Score: 4.3

Temporal Score: 3.2

Vector: CVSS2#AV:N/AC:M/Au:N/C:P/I:N/A:N

Temporal Vector: CVSS2#E:U/RL:OF/RC:C

CVSSv3

Base Score: 5.9

Temporal Score: 5.2

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

Required KB Items: Settings/PCI_DSS

Exploit Available: false

Exploit Ease: No known exploits are available

Reference Information

CVE: CVE-2013-2566, CVE-2015-2808

BID: 58796, 73684