CVE-2026-49030: Input Validation
pathe through 2.0.3 unconditionally normalizes backslash characters to forward slashes on all platforms, including POSIX systems where backslash is a valid filename character. This causes join(), resolve(), and normalize() to interpret backslash-separated dot notation sequences as directory traversal, diverging from Node.js path.posix behavior and enabling path traversal attacks that bypass common input validation in server-side applications. NOTE: the Supplier reports that "the behavior is documented, intentional, and identical in spirit to path.win32."
Other sources
Rejected reason: DO NOT USE THIS CANDIDATE NUMBER. ConsultIDs: none. Reason: This candidate was withdrawn by its CNA. Further investigation showed that it was not a security issue. Notes: none.
— NVD
Affected Software
Event History
Frequently Asked Questions
Which applications are realistically exposed to traversal through this behavior?
Server-side applications using pathe on POSIX systems are exposed if they pass attacker-controlled path input to join(), resolve(), or normalize() and rely on backslashes being treated as literal filename characters or on validation that does not account for backslash-separated dot notation.
What does an attacker need to supply to exploit the issue?
The attacker needs control over a path value processed by pathe. Backslash-separated dot notation can be normalized as directory traversal, potentially bypassing input validation that expects POSIX path semantics.
Are POSIX deployments affected by default?
Yes. The reported behavior applies on all platforms, including POSIX systems, because pathe unconditionally converts backslashes to forward slashes. Impact still depends on whether untrusted path input reaches the affected path-handling functions.
What can be done if the application cannot immediately change its dependency?
Do not pass untrusted path values directly to pathe join(), resolve(), or normalize() where POSIX semantics are required. Reject or otherwise handle backslash characters before path processing, and enforce that the resolved path remains within the intended base directory.