High severity · published Nov 17, 2021
CVE-2021-43997
FreeRTOS versions 10.2.0 through 10.4.5 do not prevent non-kernel code from calling the xPortRaisePrivilege internal function to raise privilege
7.8
CVSS
0.3%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 27% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
Freertos · Amazon
10.2.0 before 10.4.6; 10.4.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-43997
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-43997
Release Notes
https://github.com/FreeRTOS/FreeRTOS-Kernel/releases/tag/V10.4.3-LTS-Patch-2
github.com
https://github.com/FreeRTOS/FreeRTOS-Kernel/releases/tag/V10.4.3-LTS-Patch-3
Release Notes
https://github.com/FreeRTOS/FreeRTOS-Kernel/releases/tag/V10.4.6
github.com
https://github.com/FreeRTOS/FreeRTOS-Kernel/releases/tag/V10.5.0
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