IBM HTTP Server SSL/TLS RC4 Stream Cipher Key Invariance (Bar Mitzvah)

medium Nessus Plugin ID 87538
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Synopsis

The remote web server is affected by a security feature bypass vulnerability.

Description

According to its banner, the version of IBM HTTP Server running on the remote host is affected by a security feature bypass vulnerability, known as Bar Mitzvah, due to improper combination of state data with key data by the RC4 cipher algorithm during the initialization phase.
A man-in-the-middle attacker can exploit this, via a brute-force attack using LSB values, to decrypt the traffic.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Upgrade to IBM HTTP Server 7.0.0.39 / 8.0.0.11 / or 8.5.5.6 or later.

See Also

http://www-01.ibm.com/support/docview.wss?uid=swg21701072

http://www-01.ibm.com/support/docview.wss?uid=swg24039770

http://www.nessus.org/u?4bbf45ac

Plugin Details

Severity: Medium

ID: 87538

File Name: ibm_http_server_bar_mitzvah.nasl

Version: 1.6

Type: remote

Family: Web Servers

Published: 12/21/2015

Updated: 11/20/2019

Dependencies: http_version.nasl

Configuration: Enable paranoid mode

Risk Information

CVSS Score Source: CVE-2015-2808

VPR

Risk Factor: Low

Score: 2.4

CVSS v2

Risk Factor: Medium

Base Score: 4.3

Temporal Score: 3.2

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

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

Vulnerability Information

CPE: cpe:/a:ibm:http_server

Required KB Items: www/ibm-http, Settings/ParanoidReport

Exploit Ease: No known exploits are available

Patch Publication Date: 4/9/2015

Vulnerability Publication Date: 1/19/2015

Reference Information

CVE: CVE-2015-2808

BID: 73684