#VU86378 Resource exhaustion in PowerDNS Recursor - CVE-2023-50868

Vulnerability identifier: #VU86378

Vulnerability risk: Medium

CVSSv4.0: [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/U:Green]

CVE-ID: CVE-2023-50868

CWE-ID: CWE-400

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
PowerDNS Recursor
Server applications / DNS servers

Vendor: PowerDNS.COM B.V.

Description

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

The vulnerability exists due to improper input validation when processing DNSSEC related records. A remote attacker can trigger resource exhaustion by forcing the DNS server to query a specially crafted DNSSEC zone and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

PowerDNS Recursor: 2.9 - 2.9.22.6, 3.0 - 3.0-pre3, 3.1 - 3.1.7.2, 3.2, 3.3 - 3.3.3, 3.4.0 - 3.4.11, 3.5 - 3.5.3, 3.6.0 - 3.6.4, 3.7.1 - 3.7.4, 4.0.0 alpha1 - 4.0.9, 4.1.0 rc1 - 4.1.18, 4.2.0 rc1 - 4.2.5, 4.3.0 alpha1 - 4.3.7, 4.4.0 alpha1 - 4.4.8, 4.5.0 beta1 - 4.5.12, 4.6.0 alpha1 - 4.6.6, 4.7.0 rc1 - 4.7.6, 4.8.0 beta1 - 4.8.5, 4.9.0 rc1 - 4.9.2, 5.0.0 rc1 - 5.0.1

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External links
http://docs.powerdns.com/recursor/security-advisories/powerdns-advisory-2024-01.html

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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. However, proof of concept for this vulnerability is available.