CVE-2026-4295 is a vulnerability identified in AWS Kiro IDE, a development environment product, affecting all supported platforms running versions prior to 0.8.0. The root cause is improper enforcement of trust boundaries (CWE-829), where the IDE fails to correctly validate the trustworthiness of project directory files. This flaw allows a remote, unauthenticated attacker to craft malicious project directories that, when opened by a local user in the IDE, bypass workspace trust protections and lead to arbitrary code execution. The attack vector requires the attacker to have the ability to place or influence files in a project directory accessible to the user, but does not require prior authentication. The vulnerability impacts confidentiality, integrity, and availability, as arbitrary code execution could lead to data theft, system compromise, or denial of service. The CVSS v3.1 base score is 7.8, reflecting high severity with local attack vector, low attack complexity, no privileges required, but user interaction needed. No known exploits have been reported in the wild yet. The recommended remediation is upgrading to version 0.8.0 or higher, where the trust boundary enforcement has been corrected. This vulnerability is critical for organizations relying on AWS Kiro IDE for software development, as it could be leveraged to compromise developer workstations and potentially the software supply chain.

The vulnerability poses a significant risk to organizations using AWS Kiro IDE, particularly software development teams. Successful exploitation can lead to arbitrary code execution on developer machines, compromising sensitive source code, credentials, and build environments. This can result in intellectual property theft, insertion of malicious code into software builds, and potential lateral movement within corporate networks. The compromise of developer workstations can also undermine software supply chain security, affecting downstream customers and partners. Additionally, availability may be impacted if attackers disrupt IDE functionality or system stability. Given the widespread use of AWS services and the increasing adoption of cloud-based IDEs, the impact could be broad, affecting organizations of all sizes and sectors that rely on Kiro IDE for development. The requirement for user interaction (opening a malicious project directory) somewhat limits automated exploitation but does not eliminate risk, especially in environments where project directories are shared or sourced externally.

To mitigate this vulnerability, organizations should immediately upgrade all instances of AWS Kiro IDE to version 0.8.0 or later, where the trust boundary enforcement issue has been resolved. Additionally, implement strict controls on project directory sources by validating and restricting the origin of project files, especially those obtained from untrusted or external sources. Employ endpoint protection solutions capable of detecting suspicious file activities and monitor for unusual IDE behaviors. Educate developers on the risks of opening project directories from unknown or unverified sources and encourage the use of sandboxed environments for testing new projects. Incorporate code signing and integrity verification for project files where possible. Network segmentation and least privilege principles should be applied to limit the impact of any potential compromise. Regularly audit and update development tools and dependencies to ensure timely application of security patches.