CVE-2020-8618 : Security Advisory and Response
Learn about CVE-2020-8618, a vulnerability in BIND9 allowing attackers to trigger assertion failures during zone transfer, impacting versions 9.16.0 to 9.16.3. Find mitigation steps and preventive measures here.
A buffer boundary check assertion in rdataset.c can fail incorrectly during zone transfer.
Understanding CVE-2020-8618
An attacker exploiting this vulnerability can trigger an assertion failure during zone transfer, leading to a denial of service.
What is CVE-2020-8618?
This CVE involves an assertion check in BIND that can be incorrectly triggered by a large response during zone transfer, affecting versions 9.16.0 to 9.16.3.
The Impact of CVE-2020-8618
- CVSS Base Score: 4.9 (Medium)
- Attack Vector: Network
- Availability Impact: High
- Privileges Required: High
- Scope: Unchanged
Technical Details of CVE-2020-8618
Vulnerability Description
The vulnerability allows an attacker to trigger an assertion failure by sending specially crafted zone data during zone transfer.
Affected Systems and Versions
- Product: BIND9
- Vendor: ISC
- Versions: 9.16.0 to 9.16.3
Exploitation Mechanism
An attacker with permission to send zone data can exploit this vulnerability by intentionally triggering the assertion failure.
Mitigation and Prevention
Immediate Steps to Take
- Upgrade to BIND 9.16.4, the patched release closest to your current version.
Long-Term Security Practices
- Regularly update BIND to the latest version.
- Implement network segmentation to limit the impact of potential attacks.
Patching and Updates
- Apply security patches promptly to address known vulnerabilities.