ZDI 2026-09-10

ZDI-26-649: (Pwn2Own) OpenAI Codex Improper Neutralization of Control Sequences Remote Code Execution Vulnerability

CVE-2026-19591

Machine-generated analysis · WAYSCloud LLM

Exploitation requires the victim to open a crafted folder, leading to remote code execution.

Context

The advisory concerns OpenAI Codex. It describes an improper neutralization of control sequences that enables remote code execution when a user opens a malicious folder. The CVSS score is 7.8 (CVE-2026-19591).

Operator considerations

Check: Verify which systems have OpenAI Codex installed and note their versions.
Isolate: Consider restricting execution of Codex to isolated environments until mitigation is available.
Log: Log any attempts to open unexpected or newly created folders by Codex processes.

From Zero Day Initiative ↗

This vulnerability allows remote attackers to execute arbitrary code on affected installations of OpenAI Codex. User interaction is required to exploit this vulnerability in that the target must open a malicious folder. The ZDI has assigned a CVSS rating of 7.8. The following CVEs are assigned: CVE-2026-19591.

Read the full advisory on ZDI →