#VU55974 Reachable Assertion in ISC BIND - CVE-2021-25218
Published: August 18, 2021
Vulnerability identifier: #VU55974
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-2021-25218
CWE-ID: CWE-617
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
ISC BIND
ISC BIND
Software vendor:
ISC
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.
Remediation
Install updates from vendor's website.