Summary
SparkyFitness contains an OS command injection vulnerability in the administrator backup-restore endpoint, where an uploaded archive filename is incorporated into a shell command without adequate neutralization.
An authenticated global administrator who can submit a crafted restore archive may execute arbitrary operating-system commands with the privileges of the server process.
SparkyFitness contains an OS command injection vulnerability in the administrator backup-restore endpoint, where an uploaded archive filename is incorporated into a shell command without adequate neutralization.
An authenticated global administrator who can submit a crafted restore archive may execute arbitrary operating-system commands with the privileges of the server process.
Affected context
The vulnerability occurs in self-hosted SparkyFitness deployments using the administrative backup-restore functionality. It requires an uploaded restore archive whose filename is processed by the server and interpolated into a shell command without sufficient separation between data and command syntax.
The vulnerability occurs in self-hosted SparkyFitness deployments using the administrative backup-restore functionality. It requires an uploaded restore archive whose filename is processed by the server and interpolated into a shell command without sufficient separation between data and command syntax.
Exploit preconditions
- Attack surface: The
api/admin/backup/restoreendpoint - Required access: Authentication as a global administrator
- Trigger point: Processing of the uploaded restore archive and its filename
- Why exploitation is possible: Shell metacharacters in the filename can alter the intended command structure when the filename is interpolated into a command executed by the server
- Attack surface: The
api/admin/backup/restoreendpoint - Required access: Authentication as a global administrator
- Trigger point: Processing of the uploaded restore archive and its filename
- Why exploitation is possible: Shell metacharacters in the filename can alter the intended command structure when the filename is interpolated into a command executed by the server
Why this happens
The underlying issue is failure to treat an uploaded filename as untrusted data before passing it into a shell command. Concatenating user-controlled values into command strings allows shell syntax contained in the value to be interpreted by the command processor, which maps to CWE-78: Improper Neutralization of Special Elements used in an OS Command.
The underlying issue is failure to treat an uploaded filename as untrusted data before passing it into a shell command. Concatenating user-controlled values into command strings allows shell syntax contained in the value to be interpreted by the command processor, which maps to CWE-78: Improper Neutralization of Special Elements used in an OS Command.
Potential impact
- Arbitrary operating-system commands may execute with server-process privileges
- Application data and configuration could be accessed, modified, or deleted
- The host environment could be altered or used for further compromise
- Credentials, tokens, or other sensitive material may be exposed
- The service could be disrupted or used to affect connected systems
- Arbitrary operating-system commands may execute with server-process privileges
- Application data and configuration could be accessed, modified, or deleted
- The host environment could be altered or used for further compromise
- Credentials, tokens, or other sensitive material may be exposed
- The service could be disrupted or used to affect connected systems
General mitigation guidance
Mitigation generally focuses on preventing untrusted filenames and archive metadata from reaching a shell interpreter.
Common defensive patterns include:
- Use direct process-execution APIs with argument arrays rather than shell command construction
- Treat uploaded filenames as untrusted labels and replace them with server-generated identifiers
- Apply strict filename allowlists and canonicalization before storage or processing
- Validate archive contents, paths, and metadata independently of the filename
- Avoid invoking a shell when performing backup or restore operations
- Run the application with the minimum filesystem, process, and network privileges required
- Isolate restore processing from sensitive services and host resources where practical
Mitigation generally focuses on preventing untrusted filenames and archive metadata from reaching a shell interpreter.
Common defensive patterns include:
- Use direct process-execution APIs with argument arrays rather than shell command construction
- Treat uploaded filenames as untrusted labels and replace them with server-generated identifiers
- Apply strict filename allowlists and canonicalization before storage or processing
- Validate archive contents, paths, and metadata independently of the filename
- Avoid invoking a shell when performing backup or restore operations
- Run the application with the minimum filesystem, process, and network privileges required
- Isolate restore processing from sensitive services and host resources where practical
How teams detect issues like this
Organizations can look for command-injection risks through:
- Static analysis rules identifying string concatenation or interpolation passed to shell execution APIs
- Code review checks for uploaded filenames, archive metadata, and other request values used in process commands
- Runtime monitoring for unexpected child processes launched by the application
- Web and application logs showing unusual administrator restore requests or suspicious filename characters
- Policy enforcement that disallows shell invocation for file-management and archive-processing workflows
- Automated security review tools that flag tainted data flows from upload endpoints to command execution
Organizations can look for command-injection risks through:
- Static analysis rules identifying string concatenation or interpolation passed to shell execution APIs
- Code review checks for uploaded filenames, archive metadata, and other request values used in process commands
- Runtime monitoring for unexpected child processes launched by the application
- Web and application logs showing unusual administrator restore requests or suspicious filename characters
- Policy enforcement that disallows shell invocation for file-management and archive-processing workflows
- Automated security review tools that flag tainted data flows from upload endpoints to command execution
