CVE-2020-5135
Published: March 15, 2022
Official Description
A buffer overflow vulnerability in SonicOS allows a remote attacker to cause Denial of Service (DoS) and potentially execute arbitrary code by sending a malicious request to the firewall.
CISA KEV Advisory
SonicWall SonicOS Buffer Overflow Vulnerability
A buffer overflow vulnerability in SonicOS allows a remote attacker to cause Denial of Service (DoS) and potentially execute arbitrary code by sending a malicious request to the firewall.
Apply updates per vendor instructions.
Risk Analysis
This high-severity buffer overflow vulnerability in SonicOS allows a remote attacker to cause a Denial of Service (DoS) and potentially execute arbitrary code. With confirmed exploitation in the wild and an EPSS score of 0.24991, this flaw presents a critical risk for network disruption and potential system compromise. Immediate action is required.
This vulnerability is actively being exploited in the wild and is included in CISA's KEV catalog. The flaw is remotely exploitable by sending a malicious request to the firewall.
Apply all available security updates for SonicOS. Implement network segmentation and intrusion prevention systems to detect and block malicious requests targeting the firewall.
Technical Analysis
CVE-2020-5135 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires some privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
CISA has added CVE-2020-5135 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.
Exploit & PoC Resources
All References (1)
Quick Facts
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2020-5135 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
- !CISA KEV: Federal agencies must patch per BOD 22-01 timeline
- !Active exploitation confirmed — treat as P1