Out-of-bounds read in MediaTek products - CVE-2026-20421
Published: February 2, 2026
Vulnerability identifier: #VU122187
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-20421
CWE-ID: CWE-125
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: MediaTek
Affected software:
MT2735
MT6833
MT6855
MT6880
MT6890
MT8791
MT6853
MT6873
MT6875
MT6877
MT6883
MT6885
MT6889
MT6891
MT6893
MT2735
MT6833
MT6855
MT6880
MT6890
MT8791
MT6853
MT6873
MT6875
MT6877
MT6883
MT6885
MT6889
MT6891
MT6893
Detailed vulnerability description
The vulnerability allows a local application to perform a denial of service attack.
The vulnerability exists due to improper input validation in modem subcomponent. A local application can crash the system.
How to mitigate CVE-2026-20421
Install security update from vendor's website.