CVE-2020-5140 : What You Need to Know
Learn about CVE-2020-5140, a SonicOS vulnerability allowing remote attackers to cause Denial of Service (DoS) on SonicWall firewalls. Find mitigation steps and prevention measures here.
A vulnerability in SonicOS allows a remote unauthenticated attacker to cause Denial of Service (DoS) on the firewall SSLVPN service by sending a malicious HTTP request that leads to memory addresses leak. This vulnerability affected SonicOS Gen 5 version 5.9.1.7, 5.9.1.13, Gen 6 version 6.5.4.7, 6.5.1.12, 6.0.5.3, SonicOSv 6.5.4.v, and Gen 7 version SonicOS 7.0.0.0.
Understanding CVE-2020-5140
This CVE identifies a vulnerability in SonicOS that can be exploited by a remote attacker to disrupt the SSLVPN service on SonicWall firewalls.
What is CVE-2020-5140?
The vulnerability in SonicOS allows an unauthenticated remote attacker to trigger a Denial of Service (DoS) condition by exploiting a flaw in the SSLVPN service, resulting in a memory leak.
The Impact of CVE-2020-5140
The vulnerability can lead to a DoS condition on the affected firewall, potentially disrupting network operations and services.
Technical Details of CVE-2020-5140
This section provides more technical insights into the CVE.
Vulnerability Description
The vulnerability in SonicOS allows remote unauthenticated attackers to exploit the SSLVPN service, causing a DoS condition by leaking memory addresses.
Affected Systems and Versions
- SonicOS 6.5.4.7-79n and earlier
- SonicOS 5.9.1.7-2n and earlier
- SonicOS 5.9.1.13-5n and earlier
- SonicOS 6.5.1.11-4n and earlier
- SonicOS 6.0.5.3-93o and earlier
- SonicOSv 6.5.4.4-44v-21-794 and earlier
- SonicOS 7.0.0.0-1
Exploitation Mechanism
The vulnerability is exploited by sending a malicious HTTP request to the firewall SSLVPN service, leading to the leakage of memory addresses and causing a DoS condition.
Mitigation and Prevention
Protecting systems from this vulnerability is crucial to maintaining network security.
Immediate Steps to Take
- Apply patches provided by SonicWall promptly.
- Monitor network traffic for any suspicious activity.
- Implement firewall rules to restrict unauthorized access.
Long-Term Security Practices
- Regularly update and patch all software and firmware.
- Conduct security assessments and penetration testing.
- Educate users on best practices for identifying and reporting suspicious activities.
Patching and Updates
- Stay informed about security updates from SonicWall.
- Apply patches and firmware updates as soon as they are released to mitigate the risk of exploitation.