Kiro CliApplication · Amazon

CVE-2026-9255

HIGH · 7.8 CVSS v3.1 Published 2026-05-22
Fix available
A fix is available. Upgrade to 1.28.0 or later.
See remediation →
81/100
Remediation priority · High
No privileges

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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 via stdin. We recommend you to upgrade to kiro-cli version 1.28.0 or later.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

Kiro CLI before version 1.28.0 lacks proper input source validation in its tool authorization prompt mechanism. A local attacker can bypass the user approval requirement by piping specially crafted content through stdin, enabling execution of arbitrary tools and shell commands without authorization.

MitigationUpgrade kiro-cli to version 1.28.0 or later, which implements proper input source validation in the authorization prompt to prevent stdin-based bypass attacks.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Kiro CliApplication
Affected:< 1.28.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Verify Kiro CLI installation and version
    Run 'kiro --version' or 'kiro version' to retrieve the installed version number
    Affected if The installed version is below 1.28.0
  2. Check if stdin piping is in use
    Inspect how Kiro is being invoked. Look for piped input using '|' operator or redirection operators ('<') feeding content into kiro via stdin
    Affected if Content is being piped to kiro via stdin while tool execution is attempted
  3. Verify tool execution authorization is enabled
    Check kiro configuration for authorization settings. Look for config files (e.g., ~/.kiro/config) or environment variables that control tool approval prompts
    Affected if Tool execution authorization is enabled but stdin input bypasses the approval prompt
  4. Confirm vulnerability trigger condition
    Test by piping arbitrary content to kiro and attempting to execute a tool or shell command. Observe whether the authorization prompt appears or is skipped
    Affected if Commands execute without presenting an authorization prompt when input is piped via stdin

You are affected if Kiro CLI version is below 1.28.0 AND tool authorization is enabled AND input is supplied via stdin, because the approval prompt is bypassed in this configuration.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 1.28.0 or later
Fixed in 1.28.0
Interim mitigation

Upgrade kiro-cli to version 1.28.0 or later, which implements proper input source validation in the authorization prompt to prevent stdin-based bypass attacks.

Recommended fix High confidence

1.28.0

  1. Check the currently installed version of kiro-cli by running: kiro-cli --version
  2. Upgrade kiro-cli to version 1.28.0 or later using your package manager (e.g., pip install --upgrade kiro-cli, npm install -g kiro-cli, or cargo install kiro-cli depending on how it was originally installed)
  3. Verify the upgrade was successful by running: kiro-cli --version
  4. Confirm the new version is 1.28.0 or higher

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Kiro Cli Scoped from the published advisory
  • Consultation2.0 h
  • Implementation1.0 h
  • Testing2.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,060
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,696.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-9255 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-9255 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data