# CVE-2026-105811: AWS QnABot authorization bypass in Lambda hook sample

Source: https://junglewise.ai/threats/cve-2026-105811-authorization-bypass-through-a-user-controlled-key-in-the  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-06. Updated: 2026-10-06  
License: CC BY 4.0 with a link back

CVE-2026-105811 · Severity: high · CVSS 6.5 · Published 2026-10-06

QnABot on AWS is a solution for building chatbots that can answer questions using AI. An optional sample component (the Amazon Q Business Lambda hook) contains an authorization flaw that allows authenticated users to read arbitrary files from an organization's Amazon S3 storage. This affects customers who manually deployed this optional sample component.

Technologies: [Amazon AWS](https://junglewise.ai/threats/technologies/aws). Vendors: [Amazon](https://junglewise.ai/threats/vendors/amazon), [AWS](https://junglewise.ai/threats/vendors/aws).

## Quick answers

**Is CVE-2026-105811 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-105811 being exploited in the wild.

**How severe is CVE-2026-105811?** High severity, with a CVSS score of 6.5, published 6 October 2026.

**Which products and versions are affected?** AWS QnABot on AWS 7.0.0 through 7.4.5.

**Is there a fix for CVE-2026-105811?** Yes: fixed in QnABot on AWS 7.4.6 or later (with Lambda hook sample redeployed). Until then: Upgrading the QnABot on AWS stack alone is insufficient; customers must also redeploy the Amazon Q Business Lambda hook sample stack after updating to the patched version. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-105811 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-105811?** Check whether you run Amazon AWS or AWS QnABot on AWS at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- Fixed in QnABot on AWS 7.4.6 or later (with Lambda hook sample redeployed)

Upgrading the QnABot on AWS stack alone is insufficient; customers must also redeploy the Amazon Q Business Lambda hook sample stack after updating to the patched version.

## Technical details

An authorization bypass exists in the optional Amazon Q Business Lambda hook sample due to a user-controlled key parameter that is not properly validated before S3 object access. The vulnerability requires authentication and affects versions 7.0.0 through 7.4.5. Exploitation allows an authenticated remote user to read arbitrary S3 objects within the deploying AWS account.

## Affected products

- AWS QnABot on AWS 7.0.0 through 7.4.5

## Timeline

- 2026-10-06: disclosed

## References

- [https://github.com/aws-solutions-library-samples/qnabot-on-aws/releases/tag/v7.4.6](https://github.com/aws-solutions-library-samples/qnabot-on-aws/releases/tag/v7.4.6)
- [https://staging.prod.website.marketing.aws.dev/security/security-bulletins/2026-126-aws/](https://staging.prod.website.marketing.aws.dev/security/security-bulletins/2026-126-aws/)

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