CVE-2026-41429: arduino-esp32 is an Arduino core for the ESP32, ESP32-S2, ESP32-S3, ESP32-C3, ESP32-C6 and ESP32-H2 microcontrollers…
CVE-2026-41429 · Severity: high · CVSS 8.8 · Published 2026-04-24
arduino-esp32 is an Arduino core for the ESP32, ESP32-S2, ESP32-S3, ESP32-C3, ESP32-C6 and ESP32-H2 microcontrollers. Prior to 3.3.8, there is a remotely reachable memory corruption issue in the NBNS packet handling path. When NetBIOS is enabled by calling NBNS.begin(...), the device listens on UDP port 137 and processes untrusted NBNS requests from the local network.
The request parser trusts the attacker-controlled name_len field without enforcing a bound consistent with the fixed-size destination buffers used later in the flow. This vulnerability is fixed in 3.3.8.
No. Junglewise Threat Intelligence has no report of CVE-2026-41429 being exploited in the wild.
How severe is CVE-2026-41429?
High severity, with a CVSS score of 8.8, published 24 April 2026.
Which products and versions are affected?
Espressif Arduino-Esp32, Espressif Esp32, Espressif Esp32-C3, Espressif Esp32-C6 and 3 more. The advisory does not name versions.
Is there a fix for CVE-2026-41429?
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.
Am I affected by CVE-2026-41429?
Check whether you run Espressif Arduino-Esp32, Espressif Esp32, Espressif Esp32-C3 or one of the others listed. 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.