Ava-432: Denial of Service through large HTTP server response headers

Release Date

21st June 2021

Overview

If malicious HTTP server sends a response with very large headers, this can cause a stack overflow leading to a panic in the client. This impacts webhooks which make outbound connections to customer controlled servers.

Affected Products

• Ava Aware:
  • All Stable upgrade channel versions before 3.7.3
  • All Beta upgrade channel versions before 3.7.2
• Ava cameras:
  • All Stable upgrade Channel versions before 3.7.3
  • All Beta upgrade channel versions before 3.7.2

Unaffected Products

• Ava Aware:
  • All Stable upgrade channel versions after and including 3.7.3
  • All Beta upgrade channel versions after and including 3.7.2
• Ava cameras:
  • All Stable upgrade channel versions after and including 3.7.3
  • All Beta upgrade channel versions after and including 3.7.2
• Ava Cloud: all versions

Resolution

This issue has been fixed in Ava Aware Beta upgrade channel version 3.7.2 and Stable upgrade channel version 3.7.3 It is recommended that all installations running an affected version are upgraded to the latest release as soon as possible. Releases are available to download. This issue has been fixed in Ava camera Beta upgrade channel version 3.7.2 and Stable upgrade channel version 3.7.3 It is recommended that all that all Ava camera installations running an affected version upgrade to the latest release as soon as possible. Releases are available to download through the Ava Aware User Interface for Ava managed cameras and the Ava camera User Interface for unmanaged Ava cameras.

Vulnerability Information

• CVE: CVE-2021-31525
• CVSSv3 score: 3.5 Low
• CVSSv3 vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:L

Mitigations

Ensure webhook connections are made to trustworthy servers.

Workarounds

Disable webhook integration.

Acknowledgements

Issue found, and reported to the Go team, by Guido Vranken.

Disclosure Timeline

• 20/05/2021 Issue found by Guido Vranken.
• 20/05/2021 Root cause established
• 07/06/2021 Fix identified
• 17/05/2021 Patched Ava Aware (Beta upgrade channel) released
• 17/05/2021 Patched Ava cameras (Beta upgrade channel) released
• 26/05/2021 Patched Ava Aware (Stable upgrade channel) released
• 26/05/2021 Patched Ava cameras (Stable upgrade channel) released
• 21/06/2021 Vulnerability publicly disclosed