CVE-2026-105811
Received
Received - Intake
Authorization Bypass in QnABot on AWS Lambda Hook
Vulnerability report for CVE-2026-105811, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-10-06
Last updated on: 2026-10-06
Assigner: AMZN
Description
Description
Authorization bypass through a user-controlled key in the optional Amazon Q Business Lambda hook sample ( q-business-lambda-hook https://github.com/aws-solutions-library-samples/qnabot-on-aws/blob/main/source/docs/lambda_hooks/README.md ), available with QnABot on AWS versions 7.0.0 through 7.4.5, might allow an authenticated remote user to read arbitrary Amazon S3 objects in the deploying AWS account. This sample solution provides an example Lambda hook and requires separate, manual deployment and additional setup. It is not deployed automatically with QnABot. Customers who have not deployed this optional sample hook are not affected and do not need to take action.
To remediate this issue, affected customers should update the QnABot on AWS stack to version 7.4.6 or later and then redeploy the Amazon Q Business Lambda hook sample stack. Updating the QnABot on AWS stack alone does not deliver the fix.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| aws | qnabot-on-aws | 7.0.0 |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-639 | The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data. |