MediaTek MT8793 Power HAL 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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7.8$0-$5k2.29-

Summaryinfo

A vulnerability identified as very critical has been detected in MediaTek MT2718, MT6739, MT6761, MT6765, MT6768, MT6769, MT6781, MT6789, MT6833, MT6835, MT6853, MT6855, MT6858, MT6877, MT6878, MT6879, MT6881, MT6883, MT6885, MT6886, MT6889, MT6893, MT6895, MT6897, MT6899, MT6983, MT6985, MT6989, MT6991, MT6993, MT8171, MT8186, MT8188, MT8189, MT8196, MT8668, MT8676, MT8678, MT8696 and MT8793. Affected by this issue is some unknown functionality of the component Power HAL. This manipulation causes out-of-bounds write. The identification of this vulnerability is CVE-2026-20509. The attack can only be executed locally. There is no exploit available.

Detailsinfo

A vulnerability was found in MediaTek MT2718, MT6739, MT6761, MT6765, MT6768, MT6769, MT6781, MT6789, MT6833, MT6835, MT6853, MT6855, MT6858, MT6877, MT6878, MT6879, MT6881, MT6883, MT6885, MT6886, MT6889, MT6893, MT6895, MT6897, MT6899, MT6983, MT6985, MT6989, MT6991, MT6993, MT8171, MT8186, MT8188, MT8189, MT8196, MT8668, MT8676, MT8678, MT8696 and MT8793. It has been declared as very critical. Affected by this vulnerability is some unknown functionality of the component Power HAL. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. The CWE definition for the vulnerability is CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

In Power HAL, 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: ALPS11165543; Issue ID: MSV-9011.

It is possible to read the advisory at mediatek.com. This vulnerability is known as CVE-2026-20509 since 11/03/2025. The exploitation appears to be easy. Attacking locally is a requirement. Additional levels of successful authentication are needed for exploitation. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 09/07/2026).

Applying the patch ALPS11165543 is able to eliminate this problem.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-72202). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

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Vendor

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License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.2
VulDB Meta Temp Score: 7.8

VulDB Base Score: 8.2
VulDB Temp Score: 7.8
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
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: ALPS11165543

Timelineinfo

11/03/2025 CVE reserved
09/07/2026 +307 days Advisory disclosed
09/07/2026 +0 days VulDB entry created
09/07/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: mediatek.com
Status: Confirmed

CVE: CVE-2026-20509 (🔒)
GCVE (CVE): GCVE-0-2026-20509
GCVE (VulDB): GCVE-100-399499
EUVD: 🔒

Entryinfo

Created: 09/07/2026 04:16
Updated: 09/07/2026 13:32
Changes: 09/07/2026 04:16 (54), 09/07/2026 13:32 (1)
Complete: 🔍
Cache ID: 216::103

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

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