FreeRTOS Kernel up to 11.3.0 Secure Context Allocation stack size out-of-bounds write

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.7$0-$5k1.30

Summaryinfo

A vulnerability classified as problematic has been found in FreeRTOS Kernel up to 11.3.0. The affected element is an unknown function of the component Secure Context Allocation. The manipulation of the argument stack size leads to out-of-bounds write. This vulnerability is traded as CVE-2026-77236. An attack has to be approached locally. There is no exploit available.

Detailsinfo

A vulnerability was found in FreeRTOS Kernel up to 11.3.0 and classified as problematic. This issue affects some unknown processing of the component Secure Context Allocation. The manipulation of the argument stack size with an unknown input leads to a out-of-bounds write vulnerability. Using CWE to declare the problem leads to CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. Impacted is integrity, and availability. The summary by CVE is:

Missing minimum size validation in secure context allocation in FreeRTOS-Kernel before 11.3.1 might allow local users to corrupt secure-world heap metadata via an out-of-bounds write with an undersized stack size parameter. To remediate this issue, users should upgrade to version 11.3.1 or later.

The advisory is shared at aws.amazon.com. The identification of this vulnerability is CVE-2026-77236 since 08/20/2026. The exploitation is known to be easy. An attack has to be approached locally. Technical details are known, but no exploit is available.

Upgrading to version 11.3.1 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.8
VulDB Meta Temp Score: 5.7

VulDB Base Score: 4.4
VulDB Temp Score: 4.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.3
CNA Vector (AMZN): 🔒

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 11.3.1

Timelineinfo

08/20/2026 CVE reserved
08/21/2026 +1 days Advisory disclosed
08/21/2026 +0 days VulDB entry created
08/21/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: aws.amazon.com
Status: Confirmed

CVE: CVE-2026-77236 (🔒)
GCVE (CVE): GCVE-0-2026-77236
GCVE (VulDB): GCVE-100-394169

Entryinfo

Created: 08/21/2026 20:19
Changes: 08/21/2026 20:19 (76)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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