Vulnerability identifier: #VU53029
Vulnerability risk: Medium
CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]
CVE-ID:
CWE-ID:
CWE-617
Exploitation vector: Network
Exploit availability: No
Vulnerable software:
Unbound
Server applications /
DNS servers
Vendor: NLnet Labs
Description
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a reachable assertion within the dname_pkt_copy() function when processing compressed names. A remote attacker can send specially crafted data to the DNS server, trigger an assertion failure and perform a denial of service (DoS) attack.
Mitigation
Install updates from vendor's website.
Vulnerable software versions
Unbound: 1.9.0 rc1 - 1.9.4
External links
http://ostif.org/our-audit-of-unbound-dns-by-x41-d-sec-full-results/
http://lists.debian.org/debian-lts-announce/2021/05/msg00007.html
http://security.netapp.com/advisory/ntap-20210507-0007/
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.