CVE-2026-44403: Wing FTP Server < 8.1.3 Authenticated Remote Code Execution via Session Serialization

Severity: high (CVSS 7.2 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-05-12 · updated 2026-06-17
Weakness: CWE-94

Description

Wing FTP Server before 8.1.3 contains an authenticated remote code execution vulnerability in the session serialization mechanism that allows authenticated administrators to inject arbitrary Lua code through the domain admin mydirectory field. Attackers can exploit unsafe serialization of session values into Lua source code without proper escaping of closing delimiters, causing the injected code to be executed when the poisoned session is loaded via loadfile().

Affected products

Wing FTP Server: before 8.1.3 — fixed in 8.1.3

How to fix

Upgrade to a fixed version: Wing FTP Server 8.1.3. Check the vendor advisory for mitigations.

References

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