SCP12 File and Memory Management
What this means
SiteShadow flagged file-handling and memory-safety patterns that can lead to data exposure, tampering, or availability issues (path manipulation, unsafe temp files, unsafe parsing, unbounded reads).
Why it matters
File and memory issues commonly become:
- Path traversal and file disclosure (see
CWE-22/CWE-73). - Symlink/TOCTOU attacks when writing to predictable paths (see
CWE-61/CWE-362). - DoS from loading huge files into memory (see
CWE-419/CWE-400).
Safer examples
1) Enforce base directories for file access (Python)
from pathlib import Path
base = Path("/srv/uploads").resolve()
candidate = (base / filename).resolve()
if base not in candidate.parents:
raise ValueError("Invalid path")2) Use safe temp files
Use OS-managed temp APIs and avoid predictable filenames.
3) Stream large files instead of reading into memory
Process uploads/downloads in chunks; set size limits (see INPUT01-02).
How SiteShadow detects it (high level)
- Detects file operations influenced by untrusted input and missing base-dir enforcement.
- Flags unbounded reads/parsing patterns and risky temp file usage.
References
- OWASP Secure Coding Practices: https://owasp.org/www-project-secure-coding-practices-quick-reference-guide/
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