Summary
A critical command-injection vulnerability in the H3C Magic NX15's /usr/bin/usrlist component may allow a remote attacker to cause operating-system commands to execute through crafted input.
The risk is highest when the affected function is reachable over the network and user-controlled data is incorporated into a command without adequate separation or validation.
A critical command-injection vulnerability in the H3C Magic NX15's /usr/bin/usrlist component may allow a remote attacker to cause operating-system commands to execute through crafted input.
The risk is highest when the affected function is reachable over the network and user-controlled data is incorporated into a command without adequate separation or validation.
Affected context
The issue occurs in the H3C Magic NX15 100R017 firmware, within the sub_416874 function of /usr/bin/usrlist. It may be present where network-accessible functionality passes attacker-influenced values into command-processing logic without consistently treating those values as data. Exposure depends on device configuration, reachable interfaces, and the paths that invoke the affected function.
The issue occurs in the H3C Magic NX15 100R017 firmware, within the sub_416874 function of /usr/bin/usrlist. It may be present where network-accessible functionality passes attacker-influenced values into command-processing logic without consistently treating those values as data. Exposure depends on device configuration, reachable interfaces, and the paths that invoke the affected function.
Exploit preconditions
- Attack surface: A network-accessible H3C Magic NX15 service or management interface that invokes
/usr/bin/usrlist - Required access: Network reachability to the vulnerable functionality; authentication requirements may depend on deployment configuration
- Trigger point: Processing of attacker-controlled input by the
sub_416874function - Why exploitation is possible: Input may be incorporated into an operating-system command without sufficient argument separation, validation, or shell-metacharacter handling
- Attack surface: A network-accessible H3C Magic NX15 service or management interface that invokes
/usr/bin/usrlist - Required access: Network reachability to the vulnerable functionality; authentication requirements may depend on deployment configuration
- Trigger point: Processing of attacker-controlled input by the
sub_416874function - Why exploitation is possible: Input may be incorporated into an operating-system command without sufficient argument separation, validation, or shell-metacharacter handling
Why this happens
The underlying bug is command construction that allows external input to influence operating-system command execution. When application data is concatenated into a shell command or passed through an interpreter without strict control, shell syntax may be interpreted as executable instructions. This maps primarily to CWE-78: Improper Neutralization of Special Elements used in an OS Command, with CWE-77: Improper Neutralization of Special Elements in Command as a related classification.
The underlying bug is command construction that allows external input to influence operating-system command execution. When application data is concatenated into a shell command or passed through an interpreter without strict control, shell syntax may be interpreted as executable instructions. This maps primarily to CWE-78: Improper Neutralization of Special Elements used in an OS Command, with CWE-77: Improper Neutralization of Special Elements in Command as a related classification.
Potential impact
- An attacker may execute arbitrary commands with the privileges of the vulnerable service
- Device configuration, credentials, or operational data could be exposed
- Network traffic could be disrupted or redirected
- The device could be used for lateral movement or additional attacks
- Persistent compromise or unauthorized firmware and configuration changes could occur
- An attacker may execute arbitrary commands with the privileges of the vulnerable service
- Device configuration, credentials, or operational data could be exposed
- Network traffic could be disrupted or redirected
- The device could be used for lateral movement or additional attacks
- Persistent compromise or unauthorized firmware and configuration changes could occur
General mitigation guidance
Mitigation generally focuses on eliminating shell interpretation and reducing trust in externally supplied input.
Common defensive patterns include:
- Prefer direct process-execution APIs that pass fixed argument arrays rather than invoking a shell
- Apply allowlist validation for values that must be used in system operations
- Keep command names, options, and user-controlled data separate
- Run management services with the least privileges and restrict access to trusted networks
- Limit outbound connectivity and filesystem permissions for the affected service
- Use secure-by-default management interfaces and disable unnecessary exposure
- Add boundary validation before command construction, while avoiding reliance on filtering alone
Mitigation generally focuses on eliminating shell interpretation and reducing trust in externally supplied input.
Common defensive patterns include:
- Prefer direct process-execution APIs that pass fixed argument arrays rather than invoking a shell
- Apply allowlist validation for values that must be used in system operations
- Keep command names, options, and user-controlled data separate
- Run management services with the least privileges and restrict access to trusted networks
- Limit outbound connectivity and filesystem permissions for the affected service
- Use secure-by-default management interfaces and disable unnecessary exposure
- Add boundary validation before command construction, while avoiding reliance on filtering alone
How teams detect issues like this
Organizations can look for:
- Static-analysis findings involving shell invocation, command concatenation, or process execution with tainted input
- Code-review signals such as string interpolation used to build system commands
- Firmware and binary review indicators for shell calls reachable from network-parsing code
- Runtime monitoring for unexpected child processes, shell interpreters, or unusual commands spawned by management services
- Network detections for suspicious requests targeting exposed administration endpoints
- Policy checks requiring approved process-execution wrappers and input-validation controls
Automated code-review and software-composition tools may help identify risky command-execution patterns, but findings should be validated against the device's actual data flow.
Organizations can look for:
- Static-analysis findings involving shell invocation, command concatenation, or process execution with tainted input
- Code-review signals such as string interpolation used to build system commands
- Firmware and binary review indicators for shell calls reachable from network-parsing code
- Runtime monitoring for unexpected child processes, shell interpreters, or unusual commands spawned by management services
- Network detections for suspicious requests targeting exposed administration endpoints
- Policy checks requiring approved process-execution wrappers and input-validation controls
Automated code-review and software-composition tools may help identify risky command-execution patterns, but findings should be validated against the device's actual data flow.
