Vulnerability identifier: #VU703

Vulnerability risk: Medium

CVSSv3.1: 4.9 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:F/RL:O/RC:C]

CVE-ID: CVE-2016-2776

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
ISC BIND
Server applications / DNS servers
Oracle Solaris
Operating systems & Components / Operating system
Oracle Linux
Operating systems & Components / Operating system
Oracle VM Server for x86
Server applications / Other server solutions

Vendor: ISC
Oracle

Description
The vulnerability allow a remote unauthenticated user to cause denial of service (DoS) on the target system.
The weakness exists due to improper construction of queries responses, which meet certain criteria. By sending specially crafted query to the target service the attacker can trigger an assertion failure in buffer.c that leads to crash and denial of the service.
Successful exploitation of the vulnerability results in DoS condeitions on the vulnerable system.

Mitigation
Apply the following patches:

• BIND 9 version 9.9.9-P3
• BIND 9 version 9.10.4-P3
• BIND 9 version 9.11.0rc3

Vulnerable software versions

ISC BIND: 9.0 - 9.11.0

Oracle Solaris: 10 - 11.3

Oracle VM Server for x86: 3.2 - 3.4

Oracle Linux: 5

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External links
http://kb.isc.org/article/AA-01419
http://www.oracle.com/technetwork/topics/security/bulletinoct2016-3090566.html
http://www.oracle.com/technetwork/topics/security/ovmbulletinoct2016-3090547.html
http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2016-3090545.html

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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. However, a fully functional exploit for this vulnerability is available.