CVE-2026-14266 Poc: 7-Zip XZ Heap Buffer Overflow PoC Generator

Proof of Concept generator for reproducing the XZ heap buffer overflow vulnerability in 7-Zip.

The script creates a specially crafted .xz archive designed to reproduce the crash condition in the vulnerable multi-threaded XZ decompression path.

Vulnerability Information

• CVE: CVE-2026-14266
• Type: Heap Buffer Overflow
• Fixed version: 26.02 or later
• Component: XZ Decoder

Features

• Generates a valid .xz archive from scratch
• Reproduces the crash condition on vulnerable versions of 7-Zip
• No external archive generation tools required

Usage

python3 CVE-2026-14266.py

Output

poc-cve-2026-14266-crash.xz

Tested Environment

• Windows 11 x64
• 7-Zip 26.01 [https://github.com/ip7z/7zip/archive/refs/tags/26.01.zip]

References

• https://socradar.io/blog/7-zip-cve-2026-14266-rce/
• https://www.penligent.ai/hackinglabs/cve-2026-14266/
• https://mallory.ai/vulnerabilities/CVE-2026-14266