CVE-2026-5333
Remote Command Injection in DefaultFuction CMS /admin/tools.php
Publication date: 2026-04-02
Last updated on: 2026-04-29
Assigner: VulDB
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| defaultfuction | content_management_system | 1.0 |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-77 | The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component. |
| CWE-74 | The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
CVE-2026-5333 is a critical command injection vulnerability found in DefaultFuction Content-Management-System version 1.0, specifically in the file /admin/tools.php.
The vulnerability occurs because the application improperly handles user input passed directly to system shell commands without proper validation or sanitization.
Attackers can exploit this flaw by injecting arbitrary operating system commands through the 'host' parameter, allowing remote code execution (RCE) without authentication.
This can lead to full server compromise, unauthorized data access, installation of malware or backdoors, privilege escalation, lateral movement within networks, and complete takeover of the server infrastructure.
How can this vulnerability impact me? :
This vulnerability can have severe impacts including:
- Full server compromise by allowing attackers to execute arbitrary system commands remotely.
- Unauthorized access to sensitive data stored on the server.
- Installation of malware or backdoors, enabling persistent access.
- Privilege escalation, allowing attackers to gain higher-level permissions.
- Lateral movement within internal networks, potentially compromising other systems.
- Complete takeover of the server infrastructure hosting the CMS.
How can this vulnerability be detected on my network or system? Can you suggest some commands?
This vulnerability can be detected by monitoring for unusual or suspicious command execution attempts targeting the /admin/tools.php endpoint, specifically involving the host parameter.
Proof-of-Concept (PoC) HTTP GET requests demonstrate exploitation by injecting commands such as `sleep 8` or `id` via the host parameter. You can test for this vulnerability by sending crafted HTTP requests to the vulnerable endpoint and observing the response or delay.
Example commands to detect exploitation attempts include using curl or wget to send requests with injected commands:
- curl "http://<target>/admin/tools.php?host=127.0.0.1;id"
- curl "http://<target>/admin/tools.php?host=127.0.0.1;sleep 8"
Additionally, deploying Web Application Firewall (WAF) rules to detect and block command injection patterns, and monitoring logs for suspicious command execution attempts, can help detect this vulnerability.
What immediate steps should I take to mitigate this vulnerability?
Immediate mitigation steps include:
- Avoid direct execution of system shell commands with user input; use language-specific APIs or libraries that do not invoke the shell.
- Implement strict input validation with allowlists for IP addresses and domain names, rejecting inputs containing shell metacharacters such as ; & | $ ( ) < > `.
- Use parameterized commands and proper escaping functions (e.g., PHP’s escapeshellarg() and escapeshellcmd()), passing arguments as separate parameters rather than concatenated strings.
- Run the web application with least privilege, avoiding root or administrator-level execution.
- Disable dangerous PHP functions (exec, passthru, shell_exec, system, proc_open, popen, curl_exec, curl_multi_exec, parse_ini_file, show_source) via php.ini.
- Deploy Web Application Firewall (WAF) rules to detect and block command injection attempts.
- Apply network segmentation and egress filtering to isolate the application server and prevent unauthorized outbound connections.
- Conduct regular security testing such as penetration tests and integrate command injection checks into the development lifecycle (DevSecOps).
- Implement comprehensive logging and monitoring of command execution attempts with alerting on suspicious activities.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
The vulnerability allows unauthenticated remote attackers to execute arbitrary system commands, potentially resulting in full server compromise and unauthorized data access.
Such unauthorized access and potential data breaches can lead to non-compliance with common standards and regulations like GDPR and HIPAA, which require protection of sensitive personal and health information.
Failure to remediate this vulnerability could result in exposure of sensitive data, violating data protection requirements and potentially causing legal and financial consequences under these regulations.