Pachno RCE: Unrestricted File Upload Bypasses Filters
The National Vulnerability Database (NVD) recently detailed CVE-2026-40040, a high-severity vulnerability affecting Pachno version 1.0.6. This flaw, rated with a CVSS score of 8.8, stems from an unrestricted file upload mechanism that allows authenticated users to bypass the platform’s ineffective extension filtering.
Attackers can leverage this vulnerability by uploading arbitrary file types, specifically executable .php5 scripts, to the /uploadfile endpoint. Once uploaded to web-accessible directories, these malicious scripts can be executed, leading to remote code execution (RCE) on the server. This is a classic CWE-434 scenario, where insufficient validation of file uploads opens the door for serious compromise.
Related ATT&CK Techniques
🛡️ Detection Rules
5 rules · 5 SIEM formats5 auto-generated detection rules for this incident, mapped to MITRE ATT&CK. Available in Sigma, Splunk SPL, Sentinel KQL, Elastic Lucene, and QRadar AQL.
Web Application Exploitation Attempt — CVE-2026-40040
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Get Detection Rules →Indicators of Compromise
| ID | Type | Indicator |
|---|---|---|
| CVE-2026-40040 | RCE | Pachno 1.0.6 |
| CVE-2026-40040 | Unrestricted File Upload | Pachno 1.0.6, vulnerable endpoint /uploadfile, bypasses extension filtering |
| CVE-2026-40040 | Code Injection | Pachno 1.0.6, upload of .php5 scripts |
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