SSL RC4 Cipher Suites Supported (Bar Mitzvah)

medium Nessus Plugin ID 65821
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Synopsis

The remote service supports the use of the RC4 cipher.

Description

The remote host supports the use of RC4 in one or more cipher suites.
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

Reconfigure the affected application, if possible, to avoid use of RC4 ciphers. Consider using TLS 1.2 with AES-GCM suites subject to browser and web server support.

See Also

https://www.rc4nomore.com/

http://www.nessus.org/u?ac7327a0

http://cr.yp.to/talks/2013.03.12/slides.pdf

http://www.isg.rhul.ac.uk/tls/

https://www.imperva.com/docs/HII_Attacking_SSL_when_using_RC4.pdf

Plugin Details

Severity: Medium

ID: 65821

File Name: ssl_rc4_supported_ciphers.nasl

Version: 1.21

Type: remote

Family: General

Published: 4/5/2013

Updated: 2/3/2021

Dependencies: ssl_supported_ciphers.nasl

Risk Information

CVSS Score Source: CVE-2013-2566

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: Medium

Base Score: 4.3

Temporal Score: 3.7

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

Temporal Vector: E:U/RL:ND/RC:C

CVSS v3

Risk Factor: Medium

Base Score: 5.9

Temporal Score: 5.4

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

Temporal Vector: E:U/RL:X/RC:C

Vulnerability Information

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 3/12/2013

Reference Information

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

BID: 58796, 73684