What is CVE-2026-9255?

CVE-2026-9255 is a high-severity vulnerability in Amazon Kiro_cli, classified under Missing Authorization. CVSS score: 7.8/10. Published 2026-05-22.

How severe is CVE-2026-9255?

High severity. CVSS v3 base score is 7.8 out of 10.

Auth bypass in Amazon Kiro_cli

CVE-2026-9255

Missing input source validation in the tool authorization prompt in Kiro CLI before 1.28.0 allows a local attacker to execute arbitrary tools, including shell commands, without user approval by crafting content that is piped to kiro-cli vi…

Vulnerability class: Broken Access Control

EPSS: 0.000 (2.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

Affected products

Amazon Kiro_cli
Aws Kiro Cli — versions 0

Weakness classification (CWE)

CWE-862 — Missing Authorization

References

ff89ba41-3aa1-4d27-914a-91399e9639e5 (release-notes, Release Notes)
ff89ba41-3aa1-4d27-914a-91399e9639e5 (vendor-advisory, Vendor Advisory)

Frequently asked questions

What is CVE-2026-9255?: CVE-2026-9255 is a high-severity vulnerability in Amazon Kiro_cli, classified under Missing Authorization. CVSS score: 7.8/10. Published 2026-05-22.
How severe is CVE-2026-9255?: High severity. CVSS v3 base score is 7.8 out of 10.