CVE-2025-59532 is a high-severity vulnerability affecting OpenAI's Codex CLI versions 0.2.0 through 0.38.0. Codex CLI is a local coding agent that executes code generation and related tasks within a sandboxed environment to restrict file system and command execution capabilities. The vulnerability arises from improper input validation (CWE-20) in the sandbox configuration logic. Specifically, the sandbox incorrectly treats the current working directory (cwd) generated by the Codex model as the writable root of the sandbox. Because this cwd can be manipulated by the model output, it can point outside the intended workspace boundary, effectively bypassing sandbox restrictions. This flaw enables an attacker to perform arbitrary file writes and execute commands with the permissions of the Codex process, potentially compromising the host system. Notably, the network-disabled sandbox restriction remains intact, so network-based containment is unaffected. The issue was patched in Codex CLI version 0.39.0 by canonicalizing and validating the sandbox boundary to ensure it is based strictly on the user's session start directory rather than the model-generated cwd. Users of affected versions are strongly advised to update immediately, including those using the Codex IDE extension, which received a fix in version 0.4.12. The vulnerability has a CVSS 4.0 score of 8.6, reflecting its high impact on confidentiality, integrity, and availability, with low attack complexity and no required privileges or user interaction. No known exploits are currently reported in the wild. This vulnerability highlights the risks of trusting model-generated inputs for security-critical sandbox boundaries and underscores the importance of strict input validation and boundary enforcement in AI-assisted development tools.

For European organizations, this vulnerability poses significant risks, especially for software development teams and enterprises integrating Codex CLI into their development workflows. Exploitation could lead to unauthorized file system modifications, insertion of malicious code, or execution of arbitrary commands on developer machines or build servers. This can result in source code tampering, leakage of sensitive intellectual property, or compromise of internal networks if the Codex process has elevated permissions. Given that Codex CLI runs locally, the threat is particularly acute in environments where developers have access to sensitive codebases or production deployment scripts. The integrity of software supply chains could be undermined, potentially leading to downstream impacts on software products distributed across Europe. Additionally, organizations subject to strict data protection regulations (e.g., GDPR) may face compliance risks if confidential data is exposed or altered. Although network restrictions remain effective, the local privilege escalation and sandbox escape capabilities make this vulnerability a critical concern for secure development practices in European enterprises.

1. Immediate update: All users of Codex CLI versions 0.2.0 to 0.38.0 must upgrade to version 0.39.0 or later. Similarly, users of the Codex IDE extension should update to version 0.4.12 or later. 2. Verify sandbox boundaries: Organizations should audit sandbox configurations to ensure that workspace boundaries are strictly enforced and not influenced by model-generated inputs. 3. Restrict Codex permissions: Run Codex CLI processes with the least privileges necessary, ideally within isolated user accounts or containers to limit the impact of potential exploitation. 4. Monitor file system changes: Implement file integrity monitoring on developer machines and build servers to detect unauthorized modifications. 5. Educate developers: Raise awareness about the risks of using AI coding assistants and the importance of applying security patches promptly. 6. Review CI/CD pipelines: Ensure that automated build and deployment pipelines using Codex do not run with excessive privileges and incorporate security checks to detect anomalous code or commands. 7. Network segmentation: Although network restrictions are not bypassed by this vulnerability, maintaining strict network segmentation can limit lateral movement if a host is compromised.