#VU49843 Insufficient verification of data authenticity in Dnsmasq - CVE-2020-25684

Vulnerability identifier: #VU49843

Vulnerability risk: Low

CVSSv4.0: 2.9 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/U:Clear]

CVE-ID: CVE-2020-25684

CWE-ID: CWE-345

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
Dnsmasq
Server applications / DNS servers

Vendor: GNU

Description

The vulnerability allows a remote attacker to compromise the target system.

The vulnerability exists due to a lack of proper address/port check within the "reply_query" function. A remote attacker can perform a DNS cache poisoning attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Dnsmasq: before 2.83

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External links
https://ics-cert.us-cert.gov/advisories/icsa-21-019-01
https://www.jsof-tech.com/disclosures/dnspooq/

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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.