Vulnerability identifier: #VU71530

Vulnerability risk: Medium

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2022-3736

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
ISC BIND
Server applications / DNS servers

Vendor: ISC

Description

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

The vulnerability exists due to insufficient validation of user-supplied input. A remote attacker can send specially crafted RRSIG query to the DNS server and perform a denial of service (DoS) attack.

Successful exploitation of the vulnerability requires that stale cache and stale answers are enabled, option stale-answer-client-timeout is set to a positive integer, and the resolver receives an RRSIG query.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

ISC BIND: 9.16.12 - 9.19.8

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External links
http://kb.isc.org/docs/cve-2022-3736

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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.