Vulnerability identifier: #VU31359

Vulnerability risk: Medium

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

CVE-ID: CVE-2017-15105

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Unbound
Server applications / DNS servers

Vendor: NLnet Labs

Description

The vulnerability allows a remote non-authenticated attacker to manipulate data.

A flaw was found in the way unbound before 1.6.8 validated wildcard-synthesized NSEC records. An improperly validated wildcard NSEC record could be used to prove the non-existence (NXDOMAIN answer) of an existing wildcard record, or trick unbound into accepting a NODATA proof.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Unbound: 1.6.0 - 1.6.7 rc1

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External links
http://www.securityfocus.com/bid/102817
http://lists.debian.org/debian-lts-announce/2018/01/msg00039.html
http://lists.debian.org/debian-lts-announce/2019/02/msg00022.html
http://unbound.net/downloads/CVE-2017-15105.txt
http://usn.ubuntu.com/3673-1/

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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.