CVE-2020-8624 : Exploit Details and Defense Strategies
Discover the impact of CVE-2020-8624 affecting BIND versions. Learn about the vulnerability, affected systems, exploitation risks, and mitigation steps to secure your DNS infrastructure.
In BIND 9.9.12 -> 9.9.13, 9.10.7 -> 9.10.8, 9.11.3 -> 9.11.21, 9.12.1 -> 9.16.5, 9.17.0 -> 9.17.3, also affects 9.9.12-S1 -> 9.9.13-S1, 9.11.3-S1 -> 9.11.21-S1 of the BIND 9 Supported Preview Edition. An attacker with specific zone content privileges could exploit this vulnerability to modify other zone contents.
Understanding CVE-2020-8624
What is CVE-2020-8624?
This CVE involves BIND versions where a specific subset of a zone's content could be manipulated to update other parts of the zone, leading to unauthorized modifications.
The Impact of CVE-2020-8624
The vulnerability allows attackers to misuse unintended privileges, potentially altering critical DNS zone information.
Technical Details of CVE-2020-8624
Vulnerability Description
The issue arises from incorrect enforcement of "update-policy" rules, enabling unauthorized updates to various zone parts.
Affected Systems and Versions
- BIND 9.9.12 -> 9.9.13
- BIND 9.10.7 -> 9.10.8
- BIND 9.11.3 -> 9.11.21
- BIND 9.12.1 -> 9.16.5
- BIND 9.17.0 -> 9.17.3
- Also affects specific versions of BIND 9 Supported Preview Edition.
Exploitation Mechanism
Attackers with zone content privileges can exploit the vulnerability to modify unauthorized zone contents.
Mitigation and Prevention
Immediate Steps to Take
- Upgrade to the patched release closest to your current BIND version.
- Consider BIND Supported Preview Edition for eligible ISC support customers.
Long-Term Security Practices
- Regularly update BIND to the latest secure versions.
- Implement least privilege access controls to restrict unauthorized modifications.
Patching and Updates
Apply the following patches:
- BIND 9.11.22
- BIND 9.16.6
- BIND 9.17.4