Remote code execution via null-byte Lua injection
Published Jul 10, 2025 · Updated Feb 26, 2026
Code injection in Wing FTP Server before 7.4.4 allows remote attackers to execute system commands through the user or admin web interface. loginok.html authenticates only the username prefix before a null byte but saves the complete value into a Lua session file that SessionModule.load executes. Access requires valid credentials or an enabled anonymous account, and commands run as the FTP service, which uses root or SYSTEM by default.
Summary
What happened
Code injection in Wing FTP Server before 7.4.4 allows remote attackers to execute system commands through the user or admin web interface. loginok.html authenticates only the username prefix before a null byte but saves the complete value into a Lua session file that SessionModule.load executes. Access requires valid credentials or an enabled anonymous account, and commands run as the FTP service, which uses root or SYSTEM by default.
The record
- CVE
- CVE-2025-47812
- Published
- Jul 10, 2025
- Updated
- Feb 26, 2026
- Vendor
- Wing Soft Technology
- Product
- Wing FTP Server
- Classifications
- CWE-158, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 1, 2025Exploitation reportedHuntress customer exploitation incident
- Jul 10, 2025CVE publishedPublication date reported by the CVE source.
- Feb 26, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <7.4.4
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
View daily counts
| Reporting day | Unique IPs |
|---|---|
| Sep 10, 2026 | 4 |
| Sep 11, 2026 | 1 |
| Sep 12, 2026 | Unavailable |
| Sep 13, 2026 | 1 |
| Sep 14, 2026 | 1 |
| Sep 15, 2026 | Unavailable |
| Sep 16, 2026 | 2 |
Weakness, pattern, technique
Public exploit references
- Pre-auth Wing FTP Server Lua session injection exploitfunctional · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Reported exploitation
- Huntress customer exploitation incidentreported exploitation
Technologies
Your stack
See the directory against your own environment.
Your stack
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