CVE-2026-77235: CWE-416 Use after free in FreeRTOS FreeRTOS-Kernel
Description
CVE-2026-77235 is a use-after-free vulnerability in FreeRTOS-Kernel versions before 11.3.1. It arises from missing privilege verification in the secure context cleanup handler, potentially allowing local users to cause a use-after-free condition in secure-world memory via the SVC handler. This vulnerability has a high severity rating with a CVSS score of 7.3. Users should upgrade to FreeRTOS-Kernel version 11.3.1 or later to remediate the issue.
CVSS v3.1
Score 7.3high
Affected software
FreeRTOS
FreeRTOS-Kernel
pkg:github/freertos/FreeRTOS-KernelRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-77235) affects FreeRTOS-Kernel versions prior to 11.3.1. The root cause is missing privilege verification in the secure context cleanup handler, which can be triggered by local users through the SVC handler responsible for secure context deallocation. This leads to a use-after-free condition in secure-world memory, classified under CWE-416. The issue is addressed by upgrading to version 11.3.1 or later, as stated in the vendor advisory from AWS.
Potential Impact
The vulnerability allows local users with limited privileges to cause a use-after-free condition in secure-world memory, which can lead to integrity loss and high impact on availability. Confidentiality is not affected. The CVSS score of 7.3 reflects a high severity due to the potential for denial of service or system instability.
Mitigation Recommendations
A fix is available by upgrading FreeRTOS-Kernel to version 11.3.1 or later. Users should apply this official update to remediate the vulnerability. No additional mitigation steps are indicated in the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- AMZN
- Date Reserved
- 2026-08-20T18:42:39.750Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://aws.amazon.com/security/security-bulletins/2026-086-aws/","vendor":"AWS"}]
Threat ID: 6a88906bacd9273b497ffd57
Added to database: 08/21/2026, 17:52:43 UTC
Last enriched: 09/10/2026, 17:36:12 UTC
Last updated: 10/05/2026, 18:48:22 UTC
Views: 79
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