Input validation error in HAProxy

1) Input validation error

EUVDB-ID: #VU32659

Risk: Medium

CVSSv3.1: 4.6 [CVSS:3.1/CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2013-2175

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to perform service disruption.

HAProxy 1.4 before 1.4.24 and 1.5 before 1.5-dev19, when configured to use hdr_ip or other "hdr_*" functions with a negative occurrence count, allows remote attackers to cause a denial of service (negative array index usage and crash) via an HTTP header with a certain number of values, related to the MAX_HDR_HISTORY variable.

Mitigation

Install update from vendor's website.

Vulnerable software versions

HAProxy: 1.1.4 - 1.4.23

External links

http://marc.info/?l=haproxy&m=137147915029705&w=2
http://rhn.redhat.com/errata/RHSA-2013-1120.html
http://rhn.redhat.com/errata/RHSA-2013-1204.html
http://secunia.com/advisories/54344
http://www.debian.org/security/2013/dsa-2711
http://www.ubuntu.com/usn/USN-1889-1
http://bugzilla.redhat.com/show_bug.cgi?id=974259

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.