What is CVE-2021-42553?

CVE-2021-42553 is a medium-severity vulnerability in St Stm32 Mw Usb Host, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 6.8/10. Published 2022-10-21.

How severe is CVE-2021-42553?

Medium severity. CVSS v3 base score is 6.8 out of 10.

Is CVE-2021-42553 known to be exploited?

3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Buffer overflow in St Stm32 Mw Usb Host

CVE-2021-42553

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.

Vulnerability class: Buffer Overflow

EPSS: 0.010 (57.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.8 (Medium). Vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

St Stm32_mw_usb_host
Stmicroelectronics Stm32cube Stm32 Usb Host Library — versions all

Weakness classification (CWE)

CWE-120 — Buffer Copy without Checking Size of Input (Classic Buffer Overflow)

Public proof-of-concept exploits

References

vulnerability@ncsc.ch (Patch, Third Party Advisory)
vulnerability@ncsc.ch

Frequently asked questions

What is CVE-2021-42553?: CVE-2021-42553 is a medium-severity vulnerability in St Stm32 Mw Usb Host, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 6.8/10. Published 2022-10-21.
How severe is CVE-2021-42553?: Medium severity. CVSS v3 base score is 6.8 out of 10.
Is CVE-2021-42553 known to be exploited?: 3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.