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Vulnerability record · CVE-2021-27504 · published 21 November 2023

CVE-2021-27504: Amazon freertos integer overflow vulnerability

Amazon · Freertos

Texas Instruments devices running FREERTOS, malloc returns a valid pointer to a small buffer on extremely large values, which can trigger an integer overflow vulnerability in 'malloc' for FreeRTOS, resulting in code execution.

7.8 CVSS 3.1 High EPSS 0.28% · top 81.7% CWE-190 · Integer overflow
7.8CVSS 3.1 base score
0.28%EPSS exploitation probability, 30 days
NoNot in CISA KEV
6Affected product versions listed by NVD
4References
17 Jun 2026Last modified by NVD

Description

Texas Instruments devices running FREERTOS, malloc returns a valid pointer to a small buffer on extremely large values, which can trigger an integer overflow vulnerability in 'malloc' for FreeRTOS, resulting in code execution.

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

6 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://www.cisa.gov/news-events/ics-advisories/icsa-21-119-04 Third Party AdvisoryUS Government Resource
https://www.ti.com/tool/TI-RTOS-MCU Product
https://www.cisa.gov/news-events/ics-advisories/icsa-21-119-04 Third Party AdvisoryUS Government Resource
https://www.ti.com/tool/TI-RTOS-MCU Product

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.8CVE-2021-22671Ti cc3100 software development kit integer overflow vulnerabilityMultiple integer overflow issues exist while processing long domain names, which may allow an attacker to remotely execute code on the SimpleLink Wi-…EPSS 1.8%9.8CVE-2021-22679Ti cc3100 software development kit integer overflow vulnerabilityThe affected product is vulnerable to an integer overflow while processing HTTP headers, which may allow an attacker to remotely execute code on the …EPSS 1.8%9.8CVE-2021-32020Amazon freertos memory buffer overflow vulnerabilityThe kernel in Amazon Web Services FreeRTOS before 10.4.3 has insufficient bounds checking during management of heap memory.EPSS 1.3%9.8CVE-2021-31571Amazon freertos integer overflow vulnerabilityThe kernel in Amazon Web Services FreeRTOS before 10.4.3 has an integer overflow in queue.c for queue creation.EPSS 1.4%9.8CVE-2021-31572Amazon freertos integer overflow vulnerabilityThe kernel in Amazon Web Services FreeRTOS before 10.4.3 has an integer overflow in stream_buffer.c for a stream buffer.EPSS 1.4%9.3CVE-2026-77234Amazon freertos incorrect authorization vulnerabilityImproper input validation in FreeRTOS-Kernel before 11.3.1 might allow an unprivileged task on MPU-enabled ports to execute code in privileged kernel…EPSS 0.17%8.3CVE-2026-77235Amazon freertos use after free vulnerabilityMissing privilege verification in the secure context cleanup handler in FreeRTOS-Kernel before 11.3.1 might allow local users to cause a use-after-fr…EPSS 0.16%8.3CVE-2026-77236Amazon freertos out-of-bounds write vulnerabilityMissing minimum size validation in secure context allocation in FreeRTOS-Kernel before 11.3.1 might allow local users to corrupt secure-world heap me…EPSS 0.16%

Source: NIST National Vulnerability Database (record CVE-2021-27504), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.