CVE-2019-6596 Explained : Impact and Mitigation
Learn about CVE-2019-6596 affecting BIG-IP systems, leading to memory corruption and potential crashes when processing fragmented ClientHello messages in a DTLS session. Find mitigation steps and updates.
Systems running versions BIG-IP 14.0.0-14.0.0.2, 13.0.0-13.1.1.1, 12.1.0-12.1.3.6, 11.6.1-11.6.3.2, or 11.5.1-11.5.8 are at risk of memory corruption and potential crashing when processing fragmented ClientHello messages in a DTLS session. This vulnerability only affects systems that provide DTLS connections through APM.
Understanding CVE-2019-6596
In BIG-IP 14.0.0-14.0.0.2, 13.0.0-13.1.1.1, 12.1.0-12.1.3.6, 11.6.1-11.6.3.2, or 11.5.1-11.5.8, when processing fragmented ClientHello messages in a DTLS session TMM may corrupt memory eventually leading to a crash. Only systems offering DTLS connections via APM are impacted.
What is CVE-2019-6596?
- Vulnerability in BIG-IP systems leading to memory corruption and potential crashes
- Specifically occurs when processing fragmented ClientHello messages in a DTLS session
- Affects systems providing DTLS connections through APM
The Impact of CVE-2019-6596
- Risk of memory corruption and system crashes
- Potential for denial of service (DoS) attacks
Technical Details of CVE-2019-6596
This section provides detailed technical information about the vulnerability.
Vulnerability Description
- Memory corruption vulnerability in BIG-IP systems
- Triggered by processing fragmented ClientHello messages in a DTLS session
Affected Systems and Versions
- BIG-IP versions 14.0.0-14.0.0.2, 13.0.0-13.1.1.1, 12.1.0-12.1.3.6, 11.6.1-11.6.3.2, 11.5.1-11.5.8
- Systems offering DTLS connections through APM
Exploitation Mechanism
- Exploited by sending fragmented ClientHello messages in a DTLS session
- Leads to memory corruption and potential system crashes
Mitigation and Prevention
Protect your systems from CVE-2019-6596 with the following steps:
Immediate Steps to Take
- Apply vendor-supplied patches and updates
- Disable DTLS connections through APM if not required
- Monitor network traffic for any suspicious activities
Long-Term Security Practices
- Regularly update and patch BIG-IP systems
- Implement network segmentation to limit the impact of potential attacks
- Conduct regular security assessments and audits
Patching and Updates
- F5 Networks, Inc. provides patches to address the vulnerability
- Stay informed about security advisories and updates from the vendor