CVE-2026-10591: Kiro IDE Insufficient File Write Restrictions to Execution-Sensitive Paths

Synopsis

Insufficient file write restrictions in Amazon Kiro IDE (versions before 0.11) allow a remote, unauthenticated attacker to write to execution-sensitive paths such as .vscode/tasks.json. Because VS Code-style IDEs auto-execute task configurations on folder open, a crafted instruction that places a malicious tasks.json triggers arbitrary command execution on the developer's machine without further user action beyond opening a folder. A patched-image rebuild at version 0.11 is available on HarborGuard for environments running an affected version.

HarborGuard Coverage

Exploit Conditions

• Network reachabilityRequired

  The attacker delivers crafted instructions over the network to the Kiro IDE instance, so the service must be reachable remotely.

• AuthenticationNot required

  No credentials or account are needed; the vulnerability is exploitable by any unauthenticated remote actor.

• Victim interactionRequired

  A developer must open the affected folder in Kiro IDE, which triggers auto-execution of the attacker-written task configuration.

• Attack complexityDetail

  Exploitation is reliable and condition-free once the crafted file is written; no race conditions or special memory layout are required.

Blast Radius

• Attacker executes arbitrary operating system commands in the context of the developer running Kiro IDE, gaining full access to that user session.
• Confidential files accessible to the developer (source code, credentials, SSH keys, cloud tokens) are readable by the attacker.
• The attacker can modify or delete files the developer has write access to, including local repository contents and configuration files.
• Service availability for the affected developer workstation is fully disrupted if the attacker chooses to run destructive commands.