# CVE-2026-66335: AMI APTIO V heap-based buffer overflow in BIOS

Source: https://junglewise.ai/threats/cve-2026-66335-ami-aptiov-contains-vulnerabilities-in-bios-where-privileged  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-10. Updated: 2026-11-10  
License: CC BY 4.0 with a link back

CVE-2026-66335 · Severity: info · Published 2026-11-10

AMI APTIO V is a BIOS/firmware platform used in many enterprise and consumer systems. A heap-based buffer overflow vulnerability allows privileged local users to corrupt memory during firmware update processing, potentially causing the system to crash, fail updates, or compromise the confidentiality and integrity of the firmware. While a fix exists, this requires administrative access to exploit.

Technologies: [AMI Aptio V](https://junglewise.ai/threats/technologies/aptio-v). Vendors: [AMI](https://junglewise.ai/threats/vendors/ami).

## Quick answers

**Is CVE-2026-66335 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-66335 being exploited in the wild.

**How severe is CVE-2026-66335?** Informational severity, published 10 November 2026.

**Which products and versions are affected?** AMI APTIO V.

**Is there a fix for CVE-2026-66335?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-66335 attacked?** It is attacked with local access, in device firmware.

**Am I affected by CVE-2026-66335?** Check whether you run AMI Aptio V. 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.

## Technical details

A heap-based buffer overflow exists in AMI APTIO V BIOS, triggered during firmware update processing when an out-of-bounds write occurs. Exploitation requires local privileged access and may result in a denial of service (crash or failed update), or potential code execution and information disclosure. The vulnerability is a memory safety issue in the firmware update handling code.

## Affected products

- AMI APTIO V

## Timeline

- 2026-11-10: disclosed

## References

- [https://go.ami.com/hubfs/Security%20Advisories/2026/AMI-SA-2026003.pdf](https://go.ami.com/hubfs/Security%20Advisories/2026/AMI-SA-2026003.pdf)

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