Security restrictions bypass in bind (Alpine package)

1) Security restrictions bypass

EUVDB-ID: #VU7258

Risk: Medium

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

CVE-ID: CVE-2017-3143

CWE-ID: CWE-20 - Improper input validation

Exploit availability: Yes

Description

The vulnerability allows a remote attacker to bypass security restrictions on the target system.

The weakness exists due to an error in TSIG authentication of AXFR requests. A remote attacker who is able to send and receive messages to an authoritative DNS server and who has knowledge of a valid TSIG key name can send specially crafted request packet, manipulate the malicious zone content and accept unauthorized dynamic updates.

Mitigation

Install update from vendor's website.

Vulnerable software versions

bind (Alpine package): 9.6.1-r0 - 9.10.4_p8-r0

External links

http://git.alpinelinux.org/aports/commit/?id=29b8d297dd717c6b2d21833badc8e5fc3d596b37
http://git.alpinelinux.org/aports/commit/?id=071ec64d669cacbc578f4768912be8c27488ddb8
http://git.alpinelinux.org/aports/commit/?id=1bc9533e929b3ad0f241338871b7c7dd64e2d940
http://git.alpinelinux.org/aports/commit/?id=3bb085e3385115c783951d713392f492751cd08b
http://git.alpinelinux.org/aports/commit/?id=278a530682c0799cf3e11c862c4f1bce93c287e9
http://git.alpinelinux.org/aports/commit/?id=4105cc0c96fb20b95bd9f54160b62af7ca88cd72
http://git.alpinelinux.org/aports/commit/?id=678f234c682be06018570ae854e6749b50a56528
http://git.alpinelinux.org/aports/commit/?id=e049b1d35bb80fed35d73f2ddbdf64484041442d

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, proof of concept for this vulnerability is available.