Archive Member Parent Traversal Audit
Audit literal POSIX archive traversal evidence and backslash ambiguity; not a secure extraction approval or symlink defense.
Description
Audit literal POSIX archive traversal evidence and backslash ambiguity; not a secure extraction approval or symlink defense.
An archive member name can contain lexical parent traversal or ambiguous separators. These indicators are separate from proving extraction safety.
When to use this tool
Audit literal POSIX archive traversal evidence and backslash ambiguity; not a secure extraction approval or symlink defense.
- Prepare the supplied member fields for this operation.
- Compare the complete example with the representation used by your own input before carrying the result into another step.
How to use the tool and how it works
- Enter member. Use the exact text syntax, units and index conventions explained below.
- Run the tool. If input validation fails, correct the supplied fields before interpreting any result.
- Read result.absolute, result.parentComponentIndexes, result.lexicalRootEscape, result.backslashAmbiguity, result.extractionSafetyEstablished. Interpret false, null and empty lists using the distinctions below; they can be valid outputs.
Reject NUL, split on slash and ignore empty/dot components. Track lexical depth, flag a parent at depth zero, record parent component indexes and report leading slash/backslash presence. extractionSafetyEstablished is always false.1
| Input field | Meaning and representation | Accepted input |
|---|---|---|
| member | member. | Text; at most 8,192 UTF-16 code units, subject to the grammar above |
| Output field | Interpretation |
|---|---|
| result | Object containing the named outputs below. |
| result.absolute | Flag for absolute under the exact condition described above. |
| result.parentComponentIndexes | The parent component indexes list in the ordering and representation described above. |
| result.lexicalRootEscape | Flag for lexical root escape under the exact condition described above. |
| result.backslashAmbiguity | Flag for backslash ambiguity under the exact condition described above. |
| result.extractionSafetyEstablished | Always false; lexical path indicators do not establish safe archive extraction. |
{
"input": {
"member": "../a"
},
"output": {
"result": {
"absolute": false,
"parentComponentIndexes": [
0
],
"lexicalRootEscape": true,
"backslashAmbiguity": false,
"extractionSafetyEstablished": false
}
}
}Limitations and assumptions
- No archive is extracted. Symlinks, filesystem normalization, platform-specific absolute paths and destination races are not resolved; a clean lexical result is not a safe-extraction verdict.
- Every declared top-level field is required and unexpected fields are rejected. Numeric inputs must be finite; ordinary text fields are bounded to 8,192 UTF-16 code units, with tighter operation-specific limits where stated.
- String lists have at most 128 entries of at most 128 code units; matrices have at most 128 rows and columns. Larger numeric lists and parsed JSON have separate bounded budgets. Nonfinite results and excessively large serialized outputs are rejected.
- Indexes are zero-based and spans have an exclusive end unless explicitly stated otherwise. A valid false, null or empty-list result is distinct from malformed input.
Alternative or Complementary methods
Use a filesystem-aware implementation with appropriate platform semantics for actual file operations. Literal slash components, Unicode comparison and filename plans do not resolve symlinks or atomically reserve a destination.
References
Similar or alternative tools
- Path Component Common Ancestor
Find a lexical component-level common ancestor of normalized absolute POSIX paths; character-prefix and filesystem ancestry are not inferred.
- Path Component Relative Navigation
Plan lexical relative component navigation between absolute POSIX paths; no filesystem or symlink equivalence claim.