Two vulnerabilities in ModSecurity might lead to a Denial of Service.

Announced

2009-07-02

Revised

2009-07-02

Access

remote

Bugs

#262302

Advisory

https://security.gentoo.org/glsa/200907-02

Affected packages

Package	Arch	Vulnerable	Unaffected
www-apache/mod_security	*	< 2.5.9	>= 2.5.9

Background

ModSecurity is a popular web application firewall for the Apache HTTP server.

Description

Multiple vulnerabilities were discovered in ModSecurity:

• Juan Galiana Lara of ISecAuditors discovered a NULL pointer dereference when processing multipart requests without a part header name (CVE-2009-1902).
• Steve Grubb of Red Hat reported that the "PDF XSS protection" feature does not properly handle HTTP requests to a PDF file that do not use the GET method (CVE-2009-1903).

Impact

A remote attacker might send requests containing specially crafted multipart data or send certain requests to access a PDF file, possibly resulting in a Denial of Service (crash) of the Apache HTTP daemon. NOTE: The PDF XSS protection is not enabled by default.

Workaround

There is no known workaround at this time.

Resolution

All ModSecurity users should upgrade to the latest version:

# emerge --sync
# emerge --ask --oneshot --verbose ">=www-apache/mod_security-2.5.9"

References

• CVE-2009-1902
• CVE-2009-1903

A vulnerability has been discovered in mod_security, allowing a remote attacker to bypass rules.

Announced

2007-05-17

Revised

2007-12-30 (revision 2)

Access

remote

Bugs

#169778

Advisory

https://security.gentoo.org/glsa/200705-17

Affected packages

Package	Arch	Vulnerable	Unaffected
www-apache/mod_security	*	< 2.1.1	>= 2.1.1

Background

mod_security is an Apache module designed for enhancing the security of the Apache web server.

Description

Stefan Esser discovered that mod_security processes NULL characters as terminators in POST requests using the application/x-www-form-urlencoded encoding type, while other parsers used in web applications do not.

Impact

A remote attacker could send a specially crafted POST request, possibly bypassing the module ruleset and leading to the execution of arbitrary code in the scope of the web server with the rights of the user running the web server.

Workaround

There is no known workaround at this time.

Resolution

All mod_security users should upgrade to the latest version:

# emerge --sync
# emerge --ask --oneshot --verbose ">=www-apache/mod_security-2.1.1"

References

• CVE-2007-1359