#VU52736 Reachable Assertion in ISC BIND - CVE-2021-25215
Published: April 29, 2021
Vulnerability identifier: #VU52736
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-2021-25215
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 processing DNAME records. A remote attacker can force named to add the same RRset to the ANSWER section more than once, trigger an assertion failure and crash the service. Both authoritative and recursive servers are affected by this issue during zone transfers.
Remediation
Install updates from vendor's website.