Improper input validation bug in DNS resolver component of knot-resolver before 2.4.1 allows remote attacker to poison cache.
Name: Petr Spacek, the CZ.NIC team
Upstream: Marek Vavruza
[Affected version (required)]:
Knot Resolver <= 2.4.0
[Fixed version (optional)]:
Knot Resolver 2.4.1
[Vulnerability type (required)]:
CWE-20: Improper Input Validation
[Affected component (required)]:
[Impact of exploitation (required)]:
Under certain circumstances this bug allows an attacker to hijack
[Description of vulnerability]:
Improper input validation bug in DNS resolver component of Knot
Resolver allows remote attacker to poison cache.
To execute this attack the attacker has to have:
+ access to rogue authoritative server and
+ ability to trigger query from resolver under attack to authoritative
server under attacker's control
For successful exploitation the data used to poison cache need to match
certain criteria which we decided not to disclose at the moment.
Please note that "classical" DNS answer spoofing is going to be very
hard because Knot Resolver randomizes ports, query ID, and query name
capitalization - i.e. plain Kaminsky attack will be difficult. This is
why attacker needs to control an authoritative server.
Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): None
Integrity (I): High
Availability (A): None
CZ.NIC would like to thank Marek Vavrusa for reporting this issue.
[Reference URL 1 (required)]: