Critical severity · published Oct 12, 2020
CVE-2020-5135
SonicWall SonicOS Buffer Overflow Vulnerability
RansomwareIn wildKEV
9.8
CVSS
26.9%
EPSS
Yes
On KEV
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. This vulnerability affected SonicOS Gen 6 version 6.5.4.7, 6.5.1.12, 6.0.5.3, SonicOSv 6.5.4.v and Gen 7 version 7.0.0.0.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)26.9% · higher than 98% of CVEs
Exploited in the wildYes
CISA KEVListed Mar 15, 2022
Federal remediation dueApr 5, 2022
Ransomware campaign useKnown
Affected products
Which versions
SO
SonicOS · SonicWall
SonicOS 6.5.4.7-79n 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 · source: vendor, NVD, KEV
SO
Sonicosv · Sonicwall
through 6.5.4.4 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-5135
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-5135
CISA KEV catalogue
https://www.cisa.gov/known-exploited-vulnerabilities-catalog
x_refsource_CONFIRM
https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2020-0010
More from SonicOS
9.8
CVE-2024-53704
SonicWall SonicOS SSLVPN Improper Authentication Vulnerability
9.8
CVE-2024-40766
SonicWall SonicOS Improper Access Control Vulnerability
9.8
CVE-2025-40600
Use of Externally-Controlled Format String vulnerability in the SonicOS SSL VPN interface allows a remote unauthenticated attacker to cause service disruption
9.8
CVE-2024-40765
An Integer-based buffer overflow vulnerability in the SonicOS via IPSec allows a remote attacker in specific conditions to cause Denial of Service (DoS) and potentially execute…
9.8
CVE-2024-40762
Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) in the SonicOS SSLVPN authentication token generator that, in certain cases, can be predicted by an attacker…