Input validation error in GNU Dnsmasq

1) Input validation error

EUVDB-ID: #VU32274

Risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2015-8899

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.

Dnsmasq before 2.76 allows remote servers to cause a denial of service (crash) via a reply with an empty DNS address that has an (1) A or (2) AAAA record defined locally.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Dnsmasq: 2.0 - 2.75

External links

http://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2016q2/010479.html
http://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2016q2/010505.html
http://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=commit;h=41a8d9e99be9f2cc8b02051dd322cb45e0faac87
http://www.openwall.com/lists/oss-security/2016/06/03/7
http://www.openwall.com/lists/oss-security/2016/06/04/2
http://www.securityfocus.com/bid/91031
http://www.securitytracker.com/id/1036045
http://www.ubuntu.com/usn/USN-3009-1

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.