MediaTek MT6765 Vdec out-of-bounds write

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.1$0-$5k0.00

Summaryinfo

A vulnerability has been found in MediaTek MT6765, MT6768, MT6781, MT6789, MT6833, MT6853, MT6877, MT6885, MT8768, MT8771, MT8781, MT8786 and MT8791T and classified as critical. Affected by this issue is some unknown functionality of the component Vdec. Performing a manipulation results in out-of-bounds write. This vulnerability is cataloged as CVE-2025-20657. The attack must be initiated from a local position. There is no exploit available. To fix this issue, it is recommended to deploy a patch.

Detailsinfo

A vulnerability classified as critical has been found in MediaTek MT6765, MT6768, MT6781, MT6789, MT6833, MT6853, MT6877, MT6885, MT8768, MT8771, MT8781, MT8786 and MT8791T. This affects an unknown part of the component Vdec. 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 vdec, there is a possible permission bypass due to improper input validation. 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: ALPS09486425; Issue ID: MSV-2609.

It is possible to read the advisory at corp.mediatek.com. This vulnerability is uniquely identified as CVE-2025-20657 since 11/01/2024. The exploitability is told to be easy. Attacking locally is a requirement. The technical details are unknown and an exploit is not publicly available.

Applying the patch ALPS09486425 is able to eliminate this problem.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-9964). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Vendor

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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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: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: ALPS09486425

Timelineinfo

11/01/2024 🔍
04/07/2025 +156 days 🔍
04/07/2025 +0 days 🔍
10/04/2025 +180 days 🔍

Sourcesinfo

Advisory: MSV-2609
Status: Confirmed

CVE: CVE-2025-20657 (🔍)
GCVE (CVE): GCVE-0-2025-20657
GCVE (VulDB): GCVE-100-303579
EUVD: 🔍

Entryinfo

Created: 04/07/2025 07:40
Updated: 10/04/2025 20:06
Changes: 04/07/2025 07:40 (56), 10/04/2025 20:06 (1)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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