CVE-2026-20416

Local Privilege Escalation via Out‑of‑Bounds Write in PCIe Driver on MediaTek Chipsets

Published Mar 2, 2026 CVSS 3.1 · 7.2 High EPSS < 1% KEV · Not listed

Description

In pcie, there is a possible out of bounds write due to a missing bounds check. This could lead to local escalation of privilege if a malicious actor has already obtained the System privilege. User interaction is not needed for exploitation. Patch ID: ALPS10315038 / ALPS10340155; Issue ID: MSV-5155.

Analysis

Technical impact

A missing bounds check in the PCIe subsystem causes an out‑of‑bounds write that could allow a local attacker with system privileges to gain higher privileges. This flaw is a classic buffer overrun (CWE‑787) and does not require user interaction for exploitation.

Affected Systems

The vulnerability affects MediaTek chipsets MT6991, MT6993, MT8188, and MT8678, as well as Android operating system versions 15.0 and 16.0 that run on those chipsets.

Risk and Exploitability

The CVSS score of 7.2 indicates a high severity, but the EPSS score is below 1%, meaning the likelihood of current exploitation is low. Since the flaw has not been reported in the CISA KEV catalog, there is no known public exploit, yet the local escalation potential warrants prompt response. The attack would require a user already possessing system level access on the target device.

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

MediaTek, Inc.

MediaTek chipset

unaffected

Version	Status	Constraints
`MT6991`	affected	—
`MT6993`	affected	—
`MT8188`	affected	—
`MT8678`	affected	—

Configuration 1 [-]

AND

OR	cpe:2.3:o:google:android:15.0:::::::*
	cpe:2.3:o:google:android:16.0:-::::::

OR	cpe:2.3:h:mediatek:mt6991:-:::::::*
	cpe:2.3:h:mediatek:mt6993:-:::::::*
	cpe:2.3:h:mediatek:mt8188:-:::::::*
	cpe:2.3:h:mediatek:mt8678:-:::::::*

No data.

Vendor Product Versions

Mediatek

Mt6991

Version	Status	Scheme	Platform
`Android 15.0, 16.0`	affected	generic	—

Mediatek

Mt6993

Version	Status	Scheme	Platform
`Android 15.0, 16.0`	affected	generic	—

Mediatek

Mt8188

Version	Status	Scheme	Platform
`Android 15.0, 16.0`	affected	generic	—

Mediatek

Mt8678

Version	Status	Scheme	Platform
`Android 15.0, 16.0`	affected	generic	—

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

Apply the MediaTek firmware patch identified by ALPS10315038 or ALPS10340155 to the affected chipsets.
Reboot the device after installing the firmware to ensure the corrected PCIe driver is active.
Restrict non‑privileged users from accessing the PCIe subsystem by adjusting device permissions or disabling the PCIe interface for untrusted users.

Generated by OpenCVE AI on April 16, 2026 at 14:35 UTC.

Tracking

Advisories

No advisories available

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required High

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

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% (0.206% probability within 30 days)

Exploitation none

Automatable no

Technical Impact total

References

Link	Providers
https://corp.mediatek.com/product-security-bulletin/March-2026

History

Apr 16, 2026 3:00 PM Title updated View changes

Type	Values Removed	Values Added
Title		Local Privilege Escalation via Out‑of‑Bounds Write in PCIe Driver on MediaTek Chipsets

Mar 3, 2026 1:15 PM First appearance in the feed. Affected versions updated. Affected vendors updated View changes

Type	Values Removed	Values Added
First Time appeared		Google Google android Mediatek Mediatek mt6991 Mediatek mt6993 Mediatek mt8188 Mediatek mt8678
CPEs		cpe:2.3:h:mediatek:mt6991:-:::::::* cpe:2.3:h:mediatek:mt6993:-:::::::* cpe:2.3:h:mediatek:mt8188:-:::::::* cpe:2.3:h:mediatek:mt8678:-:::::::* cpe:2.3:o:google:android:15.0:::::::* cpe:2.3:o:google:android:16.0:-::::::
Vendors & Products		Google Google android Mediatek Mediatek mt6991 Mediatek mt6993 Mediatek mt8188 Mediatek mt8678

Mar 2, 2026 2:15 PM Scoring metrics updated View changes

Type	Values Removed	Values Added
Metrics		cvssV3_1 `{'score': 7.2, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H'}` ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Mar 2, 2026 9:00 AM Description updated. Weaknesses updated. Added references View changes

Type	Values Removed	Values Added
Description		In pcie, there is a possible out of bounds write due to a missing bounds check. This could lead to local escalation of privilege if a malicious actor has already obtained the System privilege. User interaction is not needed for exploitation. Patch ID: ALPS10315038 / ALPS10340155; Issue ID: MSV-5155.
Weaknesses		CWE-787
References		https://corp.mediatek.com/product-security-bulletin/March-2026