#VU49841 Heap-based buffer overflow in Dnsmasq - CVE-2020-25682

Vulnerability identifier: #VU49841

Vulnerability risk: High

CVSSv4.0: 7.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2020-25682

CWE-ID: CWE-122

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Dnsmasq
Server applications / DNS servers

Vendor: GNU

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error in "extract_name()" function when DNSSEC is enabled. A remote attacker can pass specially crafted data to the application, trigger heap-based buffer overflow and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

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.