ModSecurity < 2.7.6 Chunked Header Filter Bypass

medium Nessus Plugin ID 73962

Synopsis

The remote web application firewall may be affected by a filter bypass vulnerability.

Description

According to its banner, the version of ModSecurity installed on the remote host is prior to 2.7.6. It is, therefore, potentially affected by a filter bypass vulnerability.

A filter bypass vulnerability exists with 'modsecurity.c' not properly handling chunked requests. A remote attacker, with a specially crafted request, can bypass security filters and inject arbitrary content.

Note that Nessus has not tested for this issue but has instead relied only on the version in the server's banner.

Solution

Upgrade to ModSecurity version 2.7.6 or later.

See Also

https://github.com/SpiderLabs/ModSecurity/releases/tag/v2.7.6

http://swende.se/blog/HTTPChunked.html

http://www.nessus.org/u?88e6187f

Plugin Details

Severity: Medium

ID: 73962

File Name: modsecurity_2_7_6.nasl

Version: 1.7

Type: remote

Family: Firewalls

Published: 5/12/2014

Updated: 4/11/2022

Configuration: Enable paranoid mode, Enable thorough checks

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.2

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

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

Vulnerability Information

CPE: cpe:/a:modsecurity:modsecurity

Required KB Items: Settings/ParanoidReport, www/ModSecurity

Exploit Ease: No known exploits are available

Patch Publication Date: 12/16/2013

Vulnerability Publication Date: 9/5/2013

Reference Information

CVE: CVE-2013-5705

BID: 66552