VDB-413487 · CVE-2026-20528 · GCVE-0-2026-20528

MediaTek MT6990 ccci out-of-bounds write

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.
7.4	$0-$5k	0.53

Summaryinfo

A vulnerability marked as critical has been reported in MediaTek MT2735, MT2737, MT6813, MT6880, MT6890, MT6980D, MT6986, MT6986D, MT6988 and MT6990. This affects an unknown function of the component ccci. Performing a manipulation results in out-of-bounds write. This vulnerability is reported as CVE-2026-20528. The attack requires a local approach. No exploit exists. It is recommended to apply a patch to fix this issue.

Detailsinfo

A vulnerability classified as critical has been found in MediaTek MT2735, MT2737, MT6813, MT6880, MT6890, MT6980D, MT6986, MT6986D, MT6988 and MT6990. This affects an unknown code of the component ccci. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. CWE is classifying the issue as CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

In ccci, there is a possible out of bounds write and read due to a missing bounds check. This could lead to local information disclosure, memory corruption, crashes, or privilege escalation if a malicious actor has already obtained the System privilege. User interaction is needed for exploitation. Patch ID: ALPS11428950 (Note: For MT6880, MT6890) / ALPS10563453 (Note: For MT6980D, MT6990, MT6986, MT6986D, MT6813, MT6988) / AUTO00858766 (Note: For MT2735, MT2737); Issue ID: MSV-9893.

It is possible to read the advisory at mediatek.com. This vulnerability is uniquely identified as CVE-2026-20528 since 11/03/2025. The exploitability is told to be easy. Attacking locally is a requirement. Additional levels of successful authentication are required for exploitation. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available.

Applying the patch ALPS11428950/ALPS10563453/AUTO00858766 is able to eliminate this problem.

Be aware that VulDB is the high quality source for vulnerability data.

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: 7.7
VulDB Meta Temp Score: 7.4

VulDB Base Score: 7.7
VulDB Temp Score: 7.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined
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: 🔒

Patch: ALPS11428950/ALPS10563453/AUTO00858766

Timelineinfo

11/03/2025 CVE reserved
10/05/2026 +335 days Advisory disclosed
10/05/2026 +0 days VulDB entry created
10/05/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: mediatek.com
Status: Confirmed

CVE: CVE-2026-20528 (🔒)
GCVE (CVE): GCVE-0-2026-20528
GCVE (VulDB): GCVE-100-413487

Entryinfo

Created: 10/05/2026 04:21
Changes: 10/05/2026 04:21 (54)
Complete: 🔍
Cache ID: 216::103