Vulnerability identifier: #VU66539

Vulnerability risk: Medium

CVSSv3.1: 6.9 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N/E:U/RL:U/RC:C]

CVE-ID: CVE-2022-33991

CWE-ID: CWE-16

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
dproxy
Server applications / DNS servers

Vendor: dproxy

Description

The vulnerability allows a remote attacker to bypass implemented security restrictions.

The vulnerability exists due to dproxy forwards and caches DNS queries with the CD (aka checking disabled) bit set to 1, which in turn disables DNSSEC protection provided by upstream resolvers and allows to perform DNS cache poisoning.

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

dproxy: 0.5

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External links
http://www.usenix.org/conference/usenixsecurity22/presentation/jeitner
http://www.openwall.com/lists/oss-security/2022/08/14/3

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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.