#VU107023 Out-of-bounds write in MediaTek products - CVE-2025-20657

Vulnerability identifier: #VU107023

Vulnerability risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2025-20657

CWE-ID: CWE-787

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
MT6765
Mobile applications / Mobile firmware & hardware
MT6768
Mobile applications / Mobile firmware & hardware
MT6789
Mobile applications / Mobile firmware & hardware
MT6833
Mobile applications / Mobile firmware & hardware
MT8768
Mobile applications / Mobile firmware & hardware
MT8771
Mobile applications / Mobile firmware & hardware
MT8781
Mobile applications / Mobile firmware & hardware
MT8786
Mobile applications / Mobile firmware & hardware
MT8791T
Mobile applications / Mobile firmware & hardware
MT6781
Hardware solutions / Firmware
MT6853
Hardware solutions / Firmware
MT6877
Hardware solutions / Firmware
MT6885
Hardware solutions / Firmware

Vendor: MediaTek

Description

The vulnerability allows a local application to execute arbitrary code.

The vulnerability exists due to improper input validation within vdec. A local application can execute arbitrary code.

Mitigation
Install security update from vendor's website.

Vulnerable software versions

MT6765: All versions

MT6768: All versions

MT6781: All versions

MT6789: All versions

MT6833: All versions

MT6853: All versions

MT6877: All versions

MT6885: All versions

MT8768: All versions

MT8771: All versions

MT8781: All versions

MT8786: All versions

MT8791T: All versions

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External links
https://corp.mediatek.com/product-security-bulletin/April-2025

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.