Vulnerability identifier: #VU71749

Vulnerability risk: Medium

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

CVE-ID: CVE-2022-3488

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 repeated responses to the same query, where both responses contain ECS pseudo-options, however the first is incorrect and gets rejected by the resolver. A remote attacker controlling a malicious nameserver can respond with two responses in quick succession, each with a "CLIENT-SUBNET" pseudo-option and crash the server.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

ISC BIND: 9.11.4-S1 - 9.16.33-S1

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External links
http://kb.isc.org/docs/cve-2022-3488

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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.