VDB-348328 · CVE-2026-20440 · GCVE-0-2026-20440

MediaTek MT2718/MT6899/MT6991/MT8678/MT8793 MAE improper validation of specified index, position, or offset in input

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.6	$0-$5k	0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in MediaTek MT2718, MT6899, MT6991, MT8678 and MT8793. This affects an unknown part of the component MAE. Executing a manipulation can lead to improper validation of specified index, position, or offset in input. This vulnerability appears as CVE-2026-20440. The attack requires local access. There is no available exploit. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability classified as critical was found in MediaTek MT2718, MT6899, MT6991, MT8678 and MT8793. This vulnerability affects an unknown functionality of the component MAE. The manipulation with an unknown input leads to a improper validation of specified index, position, or offset in input vulnerability. The CWE definition for the vulnerability is CWE-1285. The product receives input that is expected to specify an index, position, or offset into an indexable resource such as a buffer or file, but it does not validate or incorrectly validates that the specified index/position/offset has the required properties. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

In MAE, 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: ALPS10431968; Issue ID: MSV-5824.

The advisory is shared for download at corp.mediatek.com. This vulnerability was named CVE-2026-20440 since 11/03/2025. The exploitation appears to be easy. The attack needs to be approached locally. Additional levels of successful authentication are necessary for exploitation. There are neither technical details nor an exploit publicly available.

Applying a patch is able to eliminate this problem.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

Chip Software

Vendor

MediaTek

Name

License

commercial

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.7
VulDB Meta Temp Score: 6.6

VulDB Base Score: 6.7
VulDB Temp Score: 6.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

ADP CISA Base Score: 6.7
ADP CISA Vector: 🔒

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

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

Exploitinginfo

Class: Improper validation of specified index, position, or offset in input
CWE: CWE-1285
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Timelineinfo

11/03/2025 CVE reserved
03/02/2026 +119 days Advisory disclosed
03/02/2026 +0 days VulDB entry created
03/04/2026 +1 days VulDB entry last update

Sourcesinfo

Advisory: corp.mediatek.com
Status: Confirmed

CVE: CVE-2026-20440 (🔒)
GCVE (CVE): GCVE-0-2026-20440
GCVE (VulDB): GCVE-100-348328

Entryinfo

Created: 03/02/2026 10:17
Updated: 03/04/2026 00:00
Changes: 03/02/2026 10:17 (53), 03/04/2026 00:00 (10)
Complete: 🔍
Cache ID: 216::103