CVE-2026-77235

Missing privilege check in SecureContext_FreeContext in FreeRTOS-Kernel

Published Aug 21, 2026 CVSS 4.0 · 8.3 High EPSS < 1% KEV · Not listed

Description

Missing privilege verification in the secure context cleanup handler in FreeRTOS-Kernel before 11.3.1 might allow local users to cause a use-after-free condition in secure-world memory via the SVC handler for secure context deallocation. To remediate this issue, users should upgrade to version 11.3.1 or later.

Analysis

Technical impact

The kernel’s SecureContext_FreeContext routine lacks a privilege check, allowing a local user to trigger a use‑after‑free condition during secure‑world memory cleanup via the SVC handler. This flaw can lead to arbitrary code execution or a denial of service within the secure partition, compromising confidentiality, integrity, or availability of protected data.

Affected Systems

FreeRTOS applications built with FreeRTOS‑Kernel versions prior to 11.3.1, including all derivatives that integrate the kernel directly.

Risk and Exploitability

The CVSS score of 8.3 indicates a high severity, and the fault is exploitable by users who can invoke the SVC handler for context deallocation. No public exploitation reports exist and the vulnerability is not listed in the CISA KEV catalog, but the EPSS score is unavailable, so the exploitation probability is unknown. Nonetheless, the local nature of the attack vector means that any device running an affected kernel constitutes a direct risk.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

FreeRTOS

FreeRTOS-Kernel

unaffected

Version	Status	Constraints
`10.2.0`	affected	≤ 11.3.0

Configuration 1 [-]

cpe:2.3:o:amazon:freertos:*:*:*:*:*:*:*:*

No data.

Vendor Product Versions

Freertos

Freertos-kernel

Version	Status	Scheme	Platform
`[10.2.0,11.3.0]`	affected	semver	—

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

Upgrade the FreeRTOS‑Kernel to version 11.3.1 or later, which adds the missing privilege check.
Revoke or restrict user privileges that allow triggering secure context deallocation via the SVC handler to prevent unauthorized use.
Employ memory sanitizers or static analysis tools to detect potential use‑after‑free patterns in the kernel code during development.

Generated by OpenCVE AI on August 21, 2026 at 19:43 UTC.

Tracking

Advisories

No advisories available

Metrics

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact Low

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact High

Subsequent System Availability Impact High

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Changed

Confidentiality Impact None

Integrity Impact Low

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.157% probability within 30 days)

Exploitation none

Automatable no

Technical Impact partial

References

Link	Providers
https://aws.amazon.com/security/security-bulletins/2026-086-aws/
https://github.com/FreeRTOS/FreeRTOS-Kernel/releases/tag/V11.3.1
https://github.com/FreeRTOS/FreeRTOS-Kernel/security/advisories/GHSA-55pf-q87x-c58c

History

Aug 27, 2026 6:00 PM Scoring metrics updated View changes

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Aug 25, 2026 5:00 PM First appearance in the feed. Affected versions updated. Affected vendors updated View changes

Type	Values Removed	Values Added
First Time appeared		Amazon Amazon freertos
CPEs		cpe:2.3:o:amazon:freertos::::::::
Vendors & Products		Amazon Amazon freertos

Aug 21, 2026 8:00 PM Added references View changes

Type	Values Removed	Values Added
References		https://github.com/FreeRTOS/FreeRTOS-Kernel/security/advisories/GHSA-55pf-q87x-c58c

Aug 21, 2026 6:15 PM Description updated View changes

Type	Values Removed	Values Added
Description	Missing privilege verification in the secure context cleanup handler in FreeRTOS-Kernel before 11.3.1 might allow local users to cause a use-after-free condition in secure-world memory via the SVC handler for secure context deallocation. To remediate this issue, users should upgrade to version 11.3.1 or later.	Missing privilege verification in the secure context cleanup handler in FreeRTOS-Kernel before 11.3.1 might allow local users to cause a use-after-free condition in secure-world memory via the SVC handler for secure context deallocation. To remediate this issue, users should upgrade to version 11.3.1 or later.

Aug 21, 2026 6:00 PM Description updated. Title updated. First appearance in the feed. Weaknesses updated. Affected versions updated. Affected vendors updated. Added references. Scoring metrics updated View changes

Type	Values Removed	Values Added
Description		Missing privilege verification in the secure context cleanup handler in FreeRTOS-Kernel before 11.3.1 might allow local users to cause a use-after-free condition in secure-world memory via the SVC handler for secure context deallocation. To remediate this issue, users should upgrade to version 11.3.1 or later.
Title		Missing privilege check in SecureContext_FreeContext in FreeRTOS-Kernel
First Time appeared		Freertos Freertos freertos-kernel
Weaknesses		CWE-416
CPEs		cpe:2.3:a:freertos:freertos-kernel::::::::
Vendors & Products		Freertos Freertos freertos-kernel
References		https://aws.amazon.com/security/security-bulletins/2026-086-aws/ https://github.com/FreeRTOS/FreeRTOS-Kernel/releases/tag/V11.3.1
Metrics		cvssV3_1 `{'score': 7.3, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:H'}` cvssV4_0 `{'score': 8.3, 'vector': 'CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:H/SA:H'}`