CVE-2021-43997
Amazon FreeRTOS 10.2.0 through 10.4.5 on the ARMv7-M and ARMv8-M MPU platforms does not prevent...
FreeRTOS versions 10.2.0 through 10.4.5 do not prevent non-kernel code from calling the xPortRaisePrivilege internal function to raise privilege. FreeRTOS versions through 10.4.6 do not prevent a third party that has already independently gained the ability to execute injected code to achieve further privilege escalation by branching directly inside a FreeRTOS MPU API wrapper function with a manually crafted stack frame. These issues affect ARMv7-M MPU ports, and ARMv8-M ports with MPU support enabled (i.e. configENABLE_MPU set to 1). These are fixed in V10.5.0 and in V10.4.3-LTS Patch 3.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
7.8
FreeRTOS versions 10.2.0 through 10.4.5 do not prevent non-kernel code from calling the xPortRaisePrivilege internal function to raise privilege. FreeRTOS versions through 10.4.6 do not prevent a third party that has already independently gained the ability to execute injected code to achieve further privilege escalation by branching directly inside a FreeRTOS MPU API wrapper function with a manually crafted stack frame. These issues affect ARMv7-M MPU ports, and ARMv8-M ports with MPU support enabled (i.e. configENABLE_MPU set to 1). These are fixed in V10.5.0 and in V10.4.3-LTS Patch 3.
- Record
CVE-2021-43997- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 7.2 High
AV:L/AC:L/Au:N/C:C/I:C/A:C - Updated
- 2026-11-02
CVE List No score
FreeRTOS versions 10.2.0 through 10.4.5 do not prevent non-kernel code from calling the xPortRaisePrivilege internal function to raise privilege. FreeRTOS versions through 10.4.6 do not prevent a third party that has already independently gained the ability to execute injected code to achieve further privilege escalation by branching directly inside a FreeRTOS MPU API wrapper function with a manually crafted stack frame. These issues affect ARMv7-M MPU ports, and ARMv8-M ports with MPU support enabled (i.e. configENABLE_MPU set to 1). These are fixed in V10.5.0 and in V10.4.3-LTS Patch 3.
- Record
CVE-2021-43997- Updated
- 2026-11-02
EUVDEUVD-2021-30857 No score
FreeRTOS versions 10.2.0 through 10.4.5 do not prevent non-kernel code from calling the xPortRaisePrivilege internal function to raise privilege. FreeRTOS versions through 10.4.6 do not prevent a third party that has already independently gained the ability to execute injected code to achieve further privilege escalation by branching directly inside a FreeRTOS MPU API wrapper function with a manually crafted stack frame. These issues affect ARMv7-M MPU ports, and ARMv8-M ports with MPU support enabled (i.e. configENABLE_MPU set to 1). These are fixed in V10.5.0 and in V10.4.3-LTS Patch 3.
- Record
EUVD-2021-30857- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-cp2g-q9qc-pm45
7.8
Amazon FreeRTOS 10.2.0 through 10.4.5 on the ARMv7-M and ARMv8-M MPU platforms does not prevent...
Amazon FreeRTOS 10.2.0 through 10.4.5 on the ARMv7-M and ARMv8-M MPU platforms does not prevent non-kernel code from calling the xPortRaisePrivilege and vPortResetPrivilege internal functions. This is fixed in 10.4.6 and in 10.4.3-LTS Patch 2.
- Record
GHSA-cp2g-q9qc-pm45- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-43997 is a high vulnerability (CVSS 7.8) in Amazon Freertos, published November 17, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.34%, the 27th percentile. No source names a fixed version.
References
github.com/FreeRTOS/FreeRTOS-Kernel/releases/tag/V10.4.3-LTS-Patch-2
github.com/FreeRTOS/FreeRTOS-Kernel/releases/tag/V10.4.6
github.com/FreeRTOS/FreeRTOS-Kernel/releases/tag/V10.5.0
github.com/FreeRTOS/FreeRTOS-Kernel/releases/tag/V10.4.3-LTS-Patch-3
nvd.nist.gov/vuln/detail/CVE-2021-43997
github.com/advisories/GHSA-cp2g-q9qc-pm45