CVE-2026-23697: Unrestricted Upload of File with Dangerous Type in Vtiger Vtiger CRM
Vtiger CRM before 8.4.0 contains an authenticated file upload vulnerability that allows low-privileged users to achieve remote code execution by uploading a .phar file containing arbitrary PHP code through the Documents module, bypassing the extension denylist in config.inc.php which omits the .phar extension. The uploaded file is stored with its original .phar extension under the web-accessible storage directory, and a misconfigured .htaccess using Apache 2.2 syntax is silently ignored on Apache 2.4 deployments, allowing unauthenticated HTTP requests to directly execute the uploaded PHP payload.
AI Analysis
Technical Summary
CVE-2026-23697 affects Vtiger CRM versions before 8.4.0 and involves an authenticated file upload vulnerability. The Documents module's file upload mechanism fails to block .phar files, which can contain arbitrary PHP code. Because the extension denylist in config.inc.php omits .phar, low-privileged users can upload malicious .phar files. These files are stored under a web-accessible storage directory with their original extension. Additionally, a misconfigured .htaccess file using Apache 2.2 syntax is ignored by Apache 2.4, allowing unauthenticated HTTP requests to execute the PHP code embedded in the .phar file, resulting in remote code execution.
Potential Impact
An attacker with low privileges can upload a malicious .phar file containing PHP code and achieve remote code execution on the server. The vulnerability bypasses file extension restrictions and leverages a misconfiguration in .htaccess files on Apache 2.4 servers, enabling unauthenticated execution of the uploaded payload. This can lead to full compromise of the affected Vtiger CRM installation.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict file upload permissions to trusted users only and review web server configurations to ensure .htaccess files are properly interpreted. Consider disabling or restricting the Documents module file upload functionality if possible.
CVE-2026-23697: Unrestricted Upload of File with Dangerous Type in Vtiger Vtiger CRM
Description
Vtiger CRM before 8.4.0 contains an authenticated file upload vulnerability that allows low-privileged users to achieve remote code execution by uploading a .phar file containing arbitrary PHP code through the Documents module, bypassing the extension denylist in config.inc.php which omits the .phar extension. The uploaded file is stored with its original .phar extension under the web-accessible storage directory, and a misconfigured .htaccess using Apache 2.2 syntax is silently ignored on Apache 2.4 deployments, allowing unauthenticated HTTP requests to directly execute the uploaded PHP payload.
CVSS v4.0
Score 8.7high
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-23697 affects Vtiger CRM versions before 8.4.0 and involves an authenticated file upload vulnerability. The Documents module's file upload mechanism fails to block .phar files, which can contain arbitrary PHP code. Because the extension denylist in config.inc.php omits .phar, low-privileged users can upload malicious .phar files. These files are stored under a web-accessible storage directory with their original extension. Additionally, a misconfigured .htaccess file using Apache 2.2 syntax is ignored by Apache 2.4, allowing unauthenticated HTTP requests to execute the PHP code embedded in the .phar file, resulting in remote code execution.
Potential Impact
An attacker with low privileges can upload a malicious .phar file containing PHP code and achieve remote code execution on the server. The vulnerability bypasses file extension restrictions and leverages a misconfiguration in .htaccess files on Apache 2.4 servers, enabling unauthenticated execution of the uploaded payload. This can lead to full compromise of the affected Vtiger CRM installation.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict file upload permissions to trusted users only and review web server configurations to ensure .htaccess files are properly interpreted. Consider disabling or restricting the Documents module file upload functionality if possible.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-01-14T22:02:15.209Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a4d2cd5c9d9e3dbe3825429
Added to database: 07/07/2026, 16:44:05 UTC
Last enriched: 07/15/2026, 11:04:16 UTC
Last updated: 08/21/2026, 22:52:11 UTC
Views: 108
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