Critical severity · published May 3, 2021
CVE-2021-32020
The kernel in Amazon Web Services FreeRTOS before 10.4.3 has insufficient bounds checking during management of heap memory
9.8
CVSS
1.3%
EPSS
No
On KEV
Description
The kernel in Amazon Web Services FreeRTOS before 10.4.3 has insufficient bounds checking during management of heap memory.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.3% · higher than 70% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
Freertos · Amazon
before 10.4.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-32020
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-32020
Patch
https://github.com/FreeRTOS/FreeRTOS-Kernel/commit/c7a9a01c94987082b223d3e59969ede64363da63
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