CVE-2020-5142 Cross-site scripting in SonicOS

What is CVE-2020-5142?

CVE-2020-5142 is a medium-severity cross-site scripting vulnerability in Sonicwall Sonicos, published on 12 Oct 2020. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

A stored cross-site scripting (XSS) vulnerability exists in the SonicOS SSLVPN web interface. A remote unauthenticated attacker is able to store and potentially execute arbitrary JavaScript code in the firewall SSLVPN portal. 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.

Weakness: CWE-79

Which versions are affected by CVE-2020-5142?

It affects 2 products.

Products include Sonicwall Sonicos, Sonicwall Sonicosv.

How do I fix CVE-2020-5142?

No fix has been published for CVE-2020-5142 yet. Limit exposure of the affected software until one is available.

Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.

Is CVE-2020-5142 being exploited?

There is no known exploitation of CVE-2020-5142 in the wild and no public exploit code.

Public exploit code: 1 proofs of concept on GitHub.

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-mm23-cj9m-mh27.