Summary
NexoPOS v6.2.4 contains a critical directory traversal vulnerability in the api/update endpoint. An attacker may access or manipulate files outside the intended directory when path input is insufficiently restricted, particularly when the endpoint is reachable and accepts attacker-controlled paths.
NexoPOS v6.2.4 contains a critical directory traversal vulnerability in the api/update endpoint. An attacker may access or manipulate files outside the intended directory when path input is insufficiently restricted, particularly when the endpoint is reachable and accepts attacker-controlled paths.
Affected context
The vulnerability occurs in NexoPOS v6.2.4 where the api/update endpoint processes file-related paths. Risk depends on the endpoint's exposure, authentication and authorization controls, filesystem permissions, and whether user-supplied path components are securely constrained to an intended directory.
The vulnerability occurs in NexoPOS v6.2.4 where the api/update endpoint processes file-related paths. Risk depends on the endpoint's exposure, authentication and authorization controls, filesystem permissions, and whether user-supplied path components are securely constrained to an intended directory.
Exploit preconditions
- Attack surface: The NexoPOS
api/updateHTTP endpoint - Required access: Access sufficient to submit requests to the endpoint; the exact requirement depends on deployment authentication and authorization
- Trigger point: Processing of attacker-influenced file or directory path input
- Why exploitation is possible: Path handling may allow traversal outside the designated directory when canonicalization and boundary validation are inadequate
- Attack surface: The NexoPOS
api/updateHTTP endpoint - Required access: Access sufficient to submit requests to the endpoint; the exact requirement depends on deployment authentication and authorization
- Trigger point: Processing of attacker-influenced file or directory path input
- Why exploitation is possible: Path handling may allow traversal outside the designated directory when canonicalization and boundary validation are inadequate
Why this happens
The underlying bug is an insufficiently constrained filesystem path derived from external input. If traversal sequences or equivalent path representations are not normalized and checked against an approved base directory, the application may resolve a path outside its intended scope. This behavior maps to CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal').
The underlying bug is an insufficiently constrained filesystem path derived from external input. If traversal sequences or equivalent path representations are not normalized and checked against an approved base directory, the application may resolve a path outside its intended scope. This behavior maps to CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal').
Potential impact
- An attacker may read sensitive files accessible to the application
- An attacker could overwrite or modify files within the service account's permissions
- Application configuration, credentials, or stored data may be exposed
- File modification could enable service disruption or further compromise
- The vulnerability may support lateral movement if exposed credentials are reused
- An attacker may read sensitive files accessible to the application
- An attacker could overwrite or modify files within the service account's permissions
- Application configuration, credentials, or stored data may be exposed
- File modification could enable service disruption or further compromise
- The vulnerability may support lateral movement if exposed credentials are reused
General mitigation guidance
Mitigation generally focuses on reducing trust in client-supplied paths and enforcing filesystem boundaries.
Common defensive patterns include:
- Resolve and canonicalize paths before use, then verify they remain under an approved directory
- Prefer server-controlled identifiers or allowlisted filenames over raw client-provided paths
- Reject traversal indicators, absolute paths, alternate separators, and unexpected encodings as defense-in-depth
- Apply strict authorization checks separately from path validation
- Run the application with the least filesystem privileges required
- Keep sensitive files outside application-writable directories and use isolated storage locations
- Log rejected path attempts and enforce suitable request and file-operation policies
Mitigation generally focuses on reducing trust in client-supplied paths and enforcing filesystem boundaries.
Common defensive patterns include:
- Resolve and canonicalize paths before use, then verify they remain under an approved directory
- Prefer server-controlled identifiers or allowlisted filenames over raw client-provided paths
- Reject traversal indicators, absolute paths, alternate separators, and unexpected encodings as defense-in-depth
- Apply strict authorization checks separately from path validation
- Run the application with the least filesystem privileges required
- Keep sensitive files outside application-writable directories and use isolated storage locations
- Log rejected path attempts and enforce suitable request and file-operation policies
How teams detect issues like this
Organizations can look for this weakness through:
- Static analysis rules identifying filesystem operations that concatenate or resolve paths from request parameters
- Code review checks for missing canonicalization, base-directory enforcement, or authorization around file operations
- Dynamic testing of path-handling behavior using traversal variants in controlled environments
- Web application firewall or API gateway policies that detect suspicious path input as a supplementary control
- Runtime monitoring for unexpected file access outside approved application directories
Organizations can look for this weakness through:
- Static analysis rules identifying filesystem operations that concatenate or resolve paths from request parameters
- Code review checks for missing canonicalization, base-directory enforcement, or authorization around file operations
- Dynamic testing of path-handling behavior using traversal variants in controlled environments
- Web application firewall or API gateway policies that detect suspicious path input as a supplementary control
- Runtime monitoring for unexpected file access outside approved application directories
Sources
| Source | Link |
|---|---|
| nexopos. | nexopos.com |
| github. | github.com/ |
