CVE-2021-42553

Publication date 21 October 2022

Last updated 1 May 2025

Ubuntu priority

Cvss 3 Severity Score

A buffer overflow vulnerability in stm32_mw_usb_host of STMicroelectronics in versions before 3.5.1 allows an attacker to execute arbitrary code when the descriptor contains more endpoints than USBH_MAX_NUM_ENDPOINTS. The library is typically integrated when using a RTOS such as FreeRTOS on STM32 MCUs.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
micropython	25.04 plucky	Needs evaluation
	24.10 oracular	Fixed 1.22.1+ds-1ubuntu0.24.10.1
	24.04 LTS noble	Fixed 1.22.1+ds-1ubuntu0.24.04.1~esm1 Ubuntu Pro
	23.10 mantic	Ignored end of life, was needs-triage
	23.04 lunar	Ignored end of life, was needs-triage
	22.10 kinetic	Ignored end of life, was needs-triage
	22.04 LTS jammy	Fixed 1.17+ds-1.1ubuntu2+esm1 Ubuntu Pro
	20.04 LTS focal	Fixed 1.12-1ubuntu0.1~esm1 Ubuntu Pro
	18.04 LTS bionic	Not in release
	16.04 LTS xenial	Ignored end of standard support
	14.04 LTS trusty	Ignored end of standard support

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Notes

ccdm94

it seems like the micropython package contains the code which is vulnerable under ports/stm32/usbhost/Core/Src/usbh_ctlreq.c.

Severity score breakdown

Parameter	Value
Base score	9.8 · Critical
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	High
Integrity impact	High
Availability impact	High
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

Related Ubuntu Security Notices (USN)

USN-7472-1
Micropython vulnerabilities
1 May 2025