trace_d8db4e4ce52d4f86a852a8138d3446fb

This source file has a known vulnerability sink in it. Traverse the codebase and report the vulnerability. You can report multiple vulnerabilities. Start from rules/rules.go and verify how non-regex rule matching is implemented, then trace into http/data.go to show how the match result is used for access decisions. Keep the report grounded in the source and explain the prefix-collision condition that lets one directory rule affect a different sibling directory with the same leading path.

{
  "executiveSummary": "The FileBrowser application contains a path-based access control bypass vulnerability due to improper prefix matching in the rule evaluation logic. The vulnerability exists in `rules/rules.go` where non-regex rules use `strings.HasPrefix()` for matching, which fails to enforce directory boundaries. This allows a rule defined for one directory (e.g., `/foo`) to inadvertently affect sibling directories sharing the same prefix (e.g., `/foobar`). Combined with the last-match-wins semantics in `http/data.go`'s `Check()` function, this can be exploited to bypass or incorrectly apply access restrictions.",
  "reports": [
    {
      "title": "Path-Based Access Control Bypass via Prefix Collision",
      "severity": "HIGH",
      "summary": "The `Rule.Matches()` function in rules/rules.go uses `strings.HasPrefix(path, r.Path)` for non-regex rules, which does not enforce directory boundary checks. This allows a rule for path `/foo` to also match `/foobar`, causing unintended access control decisions. The `Check()` function in http/data.go iterates rules with last-match-wins semantics, amplifying the impact by allowing later rules to override previous decisions based on faulty prefix matches.",
      "rootCauseAnalysis": "In rules/rules.go, the `Matches()` function for non-regex rules only checks if the path has the rule's path as a prefix without verifying that the path is actually within the intended directory. When a path like `/foobar/secret.txt` is compared against a rule with path `/foo`, `strings.HasPrefix('/foobar/secret.txt', '/foo')` returns true, even though `/foobar` is a sibling directory, not a subdirectory of `/foo`. The `Check()` function in http/data.go iterates through all rules and updates the `allow` variable whenever a rule matches, using last-match-wins semantics. This means a maliciously crafted or incorrectly configured rule path can affect access to unrelated paths that share the same prefix.",
      "impact": "An attacker or misconfigured rule can bypass intended access restrictions. For example, if a rule is set to DENY access to `/foo`, it will also deny access to `/foobar`, which may be unintended. Conversely, if a rule ALLOWS access to `/foo`, it may inadvertently allow access to `/foobar` even if there are separate DENY rules for `/foobar`. This can lead to information disclosure, unauthorized file access, or privilege escalation depending on the file structure and rule configuration.",
      "attackPath": "An administrator configures a rule like `{Regex: false, Allow: true, Path: '/shared'}` to allow access to the `/shared` directory. An attacker creates a directory `/sharedbypass` and places sensitive files there. When accessing `/sharedbypass/secret.txt`, the `Matches()` function in rules/rules.go returns true because '/sharedbypass/secret.txt' hasPrefix '/shared'. The `Check()` function sets `allow = true` based on this match, granting unauthorized access to files outside the intended `/shared` di