Vulnerability identifier: #VU56736

Vulnerability risk: High

CVSSv3.1: 8.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2016-0746

CWE-ID: CWE-416

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
nginx
Server applications / Web servers

Vendor: NGINX

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a use-after-free error when processing a crafted DNS response related to CNAME response processing within the resolver in nginx. A remote attacker can send a specially crafted DNS response to the affected server, trigger a use-after-free error and perform a denial of service attack or execute arbitrary code on the system.

Successful exploitation of the vulnerability may allow an attacker to compromise vulnerable system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

nginx: 1.8.0, 1.9.0 - 1.9.9, 1.7.0 - 1.7.12, 1.6.0 - 1.6.3, 1.5.0 - 1.5.13, 1.4.0 - 1.4.7, 1.3.0 - 1.3.16, 1.2.0 - 1.2.9, 1.1.0 - 1.1.19, 1.0.0 - 1.0.15, 0.9.0 - 0.9.7, 0.8.0 - 0.8.55, 0.7.0 - 0.7.69, 0.6.18 - 0.6.1516

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External links
http://lists.opensuse.org/opensuse-updates/2016-02/msg00042.html
http://mailman.nginx.org/pipermail/nginx/2016-January/049700.html
http://www.debian.org/security/2016/dsa-3473
http://www.securitytracker.com/id/1034869
http://www.ubuntu.com/usn/USN-2892-1
http://access.redhat.com/errata/RHSA-2016:1425
http://bto.bluecoat.com/security-advisory/sa115
http://bugzilla.redhat.com/show_bug.cgi?id=1302588
http://security.gentoo.org/glsa/201606-06

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Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

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