This vulnerability (CVE-2026-15895) involves improper neutralization of special elements used in OS commands (CWE-78) within the npm package loading component of AWS jsii-diff. Versions prior to 1.131.0 are affected. An attacker can exploit this by providing maliciously crafted package specifiers to the npm: source argument, potentially leading to arbitrary command execution in the context of the affected system. AWS has released a fixed version (1.131.0) to mitigate this issue.

Successful exploitation of this vulnerability could allow an attacker to execute arbitrary OS commands on the affected system, which may lead to unauthorized actions or compromise of the environment where jsii-diff is used. The CVSS 4.0 base score of 8.4 indicates a high impact with local attack vector, low complexity, no privileges required, user interaction needed, and high impacts on confidentiality, integrity, and availability.

Users should upgrade to AWS jsii-diff version 1.131.0 or later to remediate this vulnerability. Since this is a cloud service managed by AWS, the vendor handles remediation for the cloud-hosted components. Refer to the official AWS security bulletin at https://aws.amazon.com/security/security-bulletins/2026-057-aws/ for the latest guidance and confirmation of patch status.