manja316/faiss-security-poc

FAISS Security PoC — Arbitrary File Read/Write

For Huntr MFV Bug Bounty Submission Only

Vulnerability

FAISS OnDiskInvertedLists deserialization reads a filename from the untrusted index file and opens/mmaps it without validation.

File: malicious_file_read.index

This crafted FAISS index contains an OnDiskInvertedLists section with the filename set to /etc/passwd. When loaded with faiss.read_index(), FAISS opens and mmaps /etc/passwd.

Reproduce

import faiss
# This will attempt to open and mmap /etc/passwd
index = faiss.read_index("malicious_file_read.index")
# Process hangs or crashes — confirming the file was opened

Affected

• faiss-cpu 1.13.2 (latest) and all prior versions
• faiss/invlists/OnDiskInvertedLists.cpp lines 712-759, 268-290

Impact

• Arbitrary file read (any file readable by the process)
• Arbitrary file write (if IO_FLAG_READ_ONLY not set — the default)