How severe is CVE-2026-77235?

CVE-2026-77235 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability high.

Is CVE-2026-77235 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (4th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-77235?

CVE-2026-77235 affects Amazon Freertos. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-77235?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2026-77235 published?

CVE-2026-77235 was published on 2026-08-21 and last updated on 2026-08-27.

CVE-2026-77235

CVE-2026-77235 is a high-severity vulnerability in Amazon Freertos with a CVSS 3.x base score of 7.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-416.

Key facts

Severity: High (CVSS 3.x base score 7.3)
CVSS v4: 8.3
EPSS exploit prediction: 0% (4th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-416
Affected product: Amazon Freertos
Published: 2026-08-21
Last modified: 2026-08-27

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.

Frequently asked questions

What is CVE-2026-77235?: 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.
How severe is CVE-2026-77235?: CVE-2026-77235 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability high.
Is CVE-2026-77235 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (4th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-77235?: CVE-2026-77235 affects Amazon Freertos. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-77235?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2026-77235 published?: CVE-2026-77235 was published on 2026-08-21 and last updated on 2026-08-27.

References

Affected products (1)

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

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