Authorization Flaw in Amazon (CVE-2026-109587)
Summary
Vulnerability in Amazon (CVE-2026-109587). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
Bulletin ID: 2026-138-AWS Scope: AWS Content Type: Important (requires attention) Publication Date: 10/16/2026 10:00 AM PDT Description: FreeRTOS-Kernel is a real-time operating system kernel for microcontrollers and small microprocessors, distributed by Amazon. AWS identified two issues with the FreeRTOS-Kernel Arm Cortex-R82 (Armv8-R AArch64) MPU port, affecting multiple versions. CVE-2026-109587: incorrect authorization in the Arm Cortex-R82 MPU port. On MPU-enabled builds, the port does not correctly enforce the memory-region boundaries assigned to an unprivileged task when it passes a buffer argument to an MPU system call. Under certain conditions, an unprivileged task might read and write privileged kernel memory outside the regions assigned to it. This issue affects Arm Cortex-R82 builds with configENABLE_MPU=1; applications that do not use the FreeRTOS MPU are not affected. CVE-2026-109588: numeric truncation in the MPU buffer authorization check on the Arm Cortex-R82 MPU port. On MPU-enabled builds, the buffer-length validation does not correctly account for the full length of a buffer passed to a stream buffer system call. Under certain conditions, an unprivileged task might read or write privileged kernel memory beyond the validated buffer window. This issue affects Arm Cortex-R82 builds with configENABLE_MPU=1; applications that do not use the FreeRTOS MPU are not affected. Impacted versions: - CVE-2026-109587 (MPU region authorization): V11.3.0 and V11.3.1 (Arm C…
Source: AWS Security Bulletins NVD
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-109587 has been found in Amazon.
Successful exploitation can lead to full system takeover. CVSS score: 8.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Amazon CVE-2026-109587" on the vendor's site.
CVE-2026-109587 (Amazon) — CWE-863 / CVSS v3 8.8
Attack vector: local / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Incorrect authorization (CWE-863) exists in Amazon.
Check the vendor advisory for the affected versions of Amazon.
Severity: High (CVSS 8.8/10). Successful exploitation can lead to full system takeover.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'Amazon' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'Amazon' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
Amazonを grep し、稼働しているサービス・バージョンを把握する。 -
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
References
- AWS aws.amazon.com
- web aws.amazon.com
- web github.com
- web github.com