Attempting QNAME minimization after forwarding can lead to an assertion failure in resolver.c
CVE-2020-8621
7.5HIGH
Summary
In BIND 9.14.0 -> 9.16.5, 9.17.0 -> 9.17.3, If a server is configured with both QNAME minimization and 'forward first' then an attacker who can send queries to it may be able to trigger the condition that will cause the server to crash. Servers that 'forward only' are not affected.
Affected Version(s)
BIND9 9.14.0
References
CVSS V3.1
Score:
7.5
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged
Timeline
- 👾
Exploit known to exist
Vulnerability published
Vulnerability Reserved
Credit
ISC would like to thank Joseph Gullo for bringing this vulnerability to our attention.