CVE-2026-26399

Medium severity, CVSS 5.3. EPSS: 0.1% chance of exploitation in the next 30 days.

A stack-use-after-return issue exists in the Arduino_Core_STM32 library prior to version 1.7.0. The pwm_start() function allocates a TIM_HandleTypeDef structure on the stack and passes its address to HAL initialization routines, where it is stored in a global timer handle registry. After the function returns, interrupt service routines may dereference this dangling pointer, resulting in memory corruption.

Published 2026-04-20. Last modified 2026-06-17.