The vulnerability arises from the Kiro CLI creating session transcript and prompt history files with world‑readable permissions on macOS and Linux. An attacker who has local user privileges on the same host could read these files and obtain sensitive data such as credentials and source code. This compromises confidentiality and may enable further attacks.

Affected by Amazon Kiro CLI, formerly Amazon Q Developer CLI, versions prior to 2.27.0 on macOS and Linux. Any user executing the CLI on a shared machine before the upgrade is at risk. No specific OS versions beyond general macOS/Linux are mentioned.

The CVSS score of 6.8 indicates moderate severity. EPSS indicates very low exploitation probability, and the vulnerability is not in KEV. Exploitation requires local access to the same system; an attacker with another local account can read the session files. The risk is therefore limited to environments where users share a host but is mitigated by upgrading or adjusting permissions. The attack vector is local, and no remote compromise is possible.