CVE-2020-5136 Memory corruption in SonicOS

What is CVE-2020-5136?

CVE-2020-5136 is a medium-severity memory corruption vulnerability in Sonicwall Sonicos, published on 12 Oct 2020. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

A buffer overflow vulnerability in SonicOS allows an authenticated attacker to cause Denial of Service (DoS) in the SSL-VPN and virtual assist portal, which leads to a firewall crash. 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 7.0.0.0.

Weakness: CWE-120

Which versions are affected by CVE-2020-5136?

It affects 2 products.

Products include Sonicwall Sonicos, Sonicwall Sonicosv.

How do I fix CVE-2020-5136?

No fix has been published for CVE-2020-5136 yet. Limit exposure of the affected software until one is available.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2020-5136 being exploited?

There is no known exploitation of CVE-2020-5136 in the wild and no public exploit code.

Other vulnerabilities in Sonicwall Sonicos

• CVE-2020-5135 SonicWall SonicOS Buffer Overflow Exploited Critical 9.8
• CVE-2024-40766 SonicWall SonicOS Improper Access Control Exploited Critical 9.3
• CVE-2024-53704 SonicWall SonicOS SSLVPN Improper Authentication Exploited High 8.2
• CVE-2025-40600 Denial of service in SonicOS Critical 9.8
• CVE-2024-22394 Auth bypass in SonicOS Critical 9.8

All Sonicwall Sonicos vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-85r9-8q36-5hm5.