#VU122186 Out-of-bounds write in MediaTek products - CVE-2026-20402

Vulnerability identifier: #VU122186

Vulnerability risk: Low

CVSSv4.0: 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-2026-20402

CWE-ID: CWE-787

Exploitation vector: Local access

Exploit availability: No public exploit available

Vulnerable software:
MT2735
MT6833
MT6855
MT6880
MT6890
MT8675
MT8771
MT8791
MT8791T
MT6853
MT6873
MT6875
MT6877
MT6883
MT6885
MT6889
MT6891
MT6893
MT8797

Software vendor:
MediaTek

The vulnerability allows a local application to execute arbitrary code.

The vulnerability exists due to improper input validation in modem subcomponent. A local application can execute arbitrary code.

Install security update from vendor's website.

• https://corp.mediatek.com/product-security-bulletin/February-2026