Vulnerability identifier: #VU55974
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:
ISC BIND
Server applications /
DNS servers
Vendor: ISC
Description
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a reachable assertion when sending large responses over UDP. If named
attempts to respond over UDP
with a response that is larger than the current effective interface
maximum transmission unit (MTU), and if response-rate limiting (RRL) is
active, an assertion failure is triggered. A remote attacker can force named to trigger the assertion failure and perform a denial of service attack.
Mitigation
Install updates from vendor's website.
Vulnerable software versions
ISC BIND: 9.16.19 - 9.17.16
External links
http://kb.isc.org/v1/docs/cve-2021-25218
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.