Cyber Posture

CVE-2026-20407

Critical

Published: 02 February 2026

Published
02 February 2026
Modified
04 February 2026
KEV Added
Patch
CVSS Score 9.3 CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.0001 0.8th percentile
Risk Priority 19 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-20407 is a critical-severity Out-of-bounds Write (CWE-787) vulnerability in Mediatek Nbiot Sdk. Its CVSS base score is 9.3 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 0.8th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-16 (Memory Protection).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploitation for Privilege Escalation (T1068). What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Mandates validation of all inputs, including bounds checks, to directly prevent out-of-bounds writes in the WLAN STA driver.

prevent

Enforces memory protections like stack canaries and address space randomization to mitigate exploitation of missing bounds checks via out-of-bounds writes.

prevent

Requires timely flaw remediation through patching, such as applying WCNCR00464377, to fix the missing bounds check in the MediaTek WLAN STA driver.

MITRE ATT&CK Enterprise TechniquesAI

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
Why these techniques?

Direct local privilege escalation via exploitation of out-of-bounds write in kernel driver (CWE-787).

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

In wlan STA driver, there is a possible escalation of privilege due to a missing bounds check. This could lead to local escalation of privilege with User execution privileges needed. User interaction is not needed for exploitation. Patch ID: WCNCR00464377;…

more

Issue ID: MSV-4905.

Deeper analysisAI

CVE-2026-20407 is a high-severity vulnerability in the wlan STA driver, stemming from a missing bounds check that enables an out-of-bounds write (CWE-787). This flaw affects MediaTek's wireless LAN station driver components, potentially present in devices using MediaTek chipsets. The issue allows local escalation of privilege, as scored at CVSS 9.3 (CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H), indicating low complexity exploitation with high impact on confidentiality, integrity, and availability across a scoped change.

A local attacker with user execution privileges can exploit this vulnerability without requiring user interaction. By triggering the missing bounds check in the wlan STA driver, the attacker achieves local escalation of privilege, potentially gaining kernel-level access or higher privileges on the affected system.

MediaTek's February 2026 Product Security Bulletin addresses this issue, providing mitigation via Patch ID WCNCR00464377 for Issue ID MSV-4905. Security practitioners should apply the referenced patch to vulnerable MediaTek wlan STA driver implementations to prevent exploitation.

Details

CWE(s)

Affected Products

mediatek
nbiot sdk
≤ 3.8

CVEs Like This One

CVE-2026-20423Same product: Mediatek Mt7902
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CVE-2026-20434Same vendor: Mediatek
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CVE-2026-20432Same vendor: Mediatek
CVE-2025-20631Same vendor: Mediatek
CVE-2025-20632Same vendor: Mediatek
CVE-2025-20708Same vendor: Mediatek
CVE-2025-20646Same vendor: Mediatek
CVE-2025-20798Same vendor: Mediatek

References