SonicWall SonicOS
YES - ON THE CISA KEV LIST
CVE-2020-5135
SonicWall SonicOS Buffer Overflow Vulnerability
overdue since 2022-04-05
SonicWall: 20 entries (1.1% of all KEV entries are from this vendor); 5 added in 2026.
BOD 26-04 note: this is the date printed in the CISA catalog. A federal agency's actual deadline is set by its SSVC tier - Act (3 days), Attend (14 days), Track (60 days), or the next scheduled upgrade - counted from the KEV listing date or the date the vulnerability is identified in its environment, whichever comes first. Use the tier helper on each CVE page for your own window.
Your BOD 26-04 window (SSVC tier helper)
Your remediation window ends:
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.
Required action (CISA)
Apply updates per vendor instructions.
Notes
https://nvd.nist.gov/vuln/detail/CVE-2020-5135
References
Other KEV entries for this vendor: SonicWall
- CVE-2026-19868 - SonicOS SSLVPN (2026-11-06)
- CVE-2026-83548 - SMA1000 Appliances (2026-09-02)
- CVE-2026-83549 - SMA1000 Appliances (2026-09-02)
- CVE-2026-15409 - SMA1000 Appliances (2026-07-14)
- CVE-2026-15410 - SMA1000 Appliances (2026-07-14)
- CVE-2025-40602 - SMA1000 appliance (2025-12-17)
- CVE-2023-44221 - SMA100 Appliances (2025-05-01)
- CVE-2021-20035 - SMA100 Appliances (2025-04-16)
Go deeper
KEV deadlines are a governance problem as much as a patching one. TrebSec's AI governance packs help small teams document, assign, and evidence exactly this work.
AI Governance Policy Pack - $79 AI Vendor Workbook - $49 Both packs bundled - $99