CVE-2020-3555 : What You Need to Know
Learn about CVE-2020-3555, a vulnerability in Cisco ASA & FTD Software allowing remote attackers to cause a denial of service. Find mitigation steps and patching details here.
A vulnerability in the SIP inspection process of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could lead to a denial of service (DoS) attack.
Understanding CVE-2020-3555
This CVE involves a vulnerability in Cisco ASA and FTD Software that could allow a remote attacker to crash and reload affected devices, causing a DoS condition.
What is CVE-2020-3555?
The vulnerability arises from a watchdog timeout and crash during the cleanup of threads associated with a SIP connection being deleted, triggered by a high rate of crafted SIP traffic.
The Impact of CVE-2020-3555
- An unauthenticated attacker can exploit the vulnerability remotely, leading to a crash and reload of the affected device.
- This could result in a denial of service condition, impacting the availability of the device.
Technical Details of CVE-2020-3555
This section provides more in-depth technical insights into the vulnerability.
Vulnerability Description
- The vulnerability allows an attacker to cause a crash and reload of affected devices through crafted SIP traffic.
Affected Systems and Versions
- Cisco Adaptive Security Appliance (ASA) Software
- Cisco Firepower Threat Defense (FTD) Software
Exploitation Mechanism
- Attack Complexity: High
- Attack Vector: Network
- Availability Impact: High
- Base Score: 6.8 (Medium Severity)
Mitigation and Prevention
Protecting systems from CVE-2020-3555 requires immediate actions and long-term security practices.
Immediate Steps to Take
- Apply vendor-provided patches and updates promptly.
- Monitor network traffic for any signs of suspicious SIP activity.
- Implement network segmentation to limit the impact of potential attacks.
Long-Term Security Practices
- Regularly update and patch all software and firmware.
- Conduct security assessments and penetration testing to identify vulnerabilities.
Patching and Updates
- Cisco has released patches to address this vulnerability. Ensure all affected systems are updated with the latest security fixes.