#VU28161 Input validation error in Unbound - CVE-2020-12662
Published: May 21, 2020
Vulnerability identifier: #VU28161
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:U/U:Green
CVE-ID: CVE-2020-12662
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
Unbound
Unbound
Software vendor:
NLnet Labs
NLnet Labs
Description
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to insufficient validation of user-supplied input when processing DNS responses. A remote attacker who controls a malicious DNS server can send a specially crafted response and perform a denial of service (DoS) attack against third-party DNS servers.
The attack is triggered by random subdomains in the NSDNAME in NS records.
Remediation
Install updates from vendor's website.