# CVE-2026-17054: Espressif ESP-hosted Wi-Fi driver out-of-bounds read in control frame parsing

Source: https://junglewise.ai/threats/cve-2026-17054-the-espressif-esp-hosted-wi-fi-driver-drivers-wifi-esp-hosted  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-21. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-17054 · Severity: medium · CVSS 5.3 · Published 2026-09-21

The ESP-hosted Wi-Fi driver in Zephyr RTOS parses control frames received from an ESP co-processor without validating the declared data length, allowing a local attacker on the same wireless network to trigger out-of-bounds memory reads by crafting malformed frame headers or exploiting SPI communication quirks. This leads to device crashes and permanent loss of Wi-Fi connectivity until reboot, effectively causing a denial-of-service condition for networked IoT devices relying on this driver.

Vendors: [Espressif](https://junglewise.ai/threats/vendors/espressif).

## Quick answers

**Is CVE-2026-17054 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-17054 being exploited in the wild.

**How severe is CVE-2026-17054?** Medium severity, with a CVSS score of 5.3, published 21 September 2026.

**Which products and versions are affected?** Espressif ESP-hosted Wi-Fi driver.

**Is there a fix for CVE-2026-17054?** 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-2026-17054 attacked?** It is attacked from the adjacent network, in a software library.

**Am I affected by CVE-2026-17054?** Check whether you run Espressif ESP-hosted Wi-Fi driver. 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

The vulnerability exists in esp_hosted_event_task(), which accepts a 16-bit TLV data_length field directly from the SPI frame without bounds checking and passes it to pb_istream_from_buffer() on a 3188-byte stack buffer, enabling reads up to ~62 KB past the buffer. Fragment reassembly bugs and unhandled control event queueing complete the denial of service: a broken reassembly guard sized incorrectly causes the RX thread to return early, while unhandled events block the message queue indefinitely, halting all Wi-Fi reception.

## Affected products

- Espressif ESP-hosted Wi-Fi driver

## Timeline

- 2026-09-21: disclosed