CVE-2026-3439 Memory corruption in SonicOS

What is CVE-2026-3439?

CVE-2026-3439 is a medium-severity memory corruption vulnerability in Sonicwall Sonicos, published on 4 Mar 2026. An attacker needs administrator access to exploit it, with no action from the victim.

Official description

A post-authentication Stack-based Buffer Overflow vulnerability in SonicOS certificate handling allows a remote attacker to crash a firewall.

Weakness: CWE-121

Which versions are affected by CVE-2026-3439?

It affects 1 product.

Products include Sonicwall Sonicos.

How do I fix CVE-2026-3439?

No fix has been published for CVE-2026-3439 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-2026-3439 being exploited?

There is no known exploitation of CVE-2026-3439 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-m887-q6ph-8x46.