Out-of-bounds write in MediaTek products - CVE-2026-20458
Published: July 1, 2026
Vulnerability identifier: #VU136040
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-20458
CWE-ID: CWE-787
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: MediaTek
Affected software:
MT8768
MT6988
MT6989
MT6990
MT6991
MT6993
MT8666
MT8667
MT8668
MT8673
MT8676
MT8678
MT8755
MT8765
MT8766
MT8766R
MT6986D
MT8775
MT8781
MT8786
MT8788
MT8788E
MT8789
MT8792
MT8793
MT8795T
MT8796
MT8798
MT8863
MT8873
MT8883
MT8893
MT6813
MT2737
MT6739
MT6761
MT6762
MT6763
MT6765
MT6767
MT6768
MT6769
MT6771
MT6783
MT6789
MT2716
MT6835
MT6858
MT6878
MT6879
MT6881
MT6886
MT6895
MT6896
MT6897
MT6899
MT6980
MT6982
MT6983
MT6985
MT6986
MT6779
MT6781
MT6785
MT8768
MT6988
MT6989
MT6990
MT6991
MT6993
MT8666
MT8667
MT8668
MT8673
MT8676
MT8678
MT8755
MT8765
MT8766
MT8766R
MT6986D
MT8775
MT8781
MT8786
MT8788
MT8788E
MT8789
MT8792
MT8793
MT8795T
MT8796
MT8798
MT8863
MT8873
MT8883
MT8893
MT6813
MT2737
MT6739
MT6761
MT6762
MT6763
MT6765
MT6767
MT6768
MT6769
MT6771
MT6783
MT6789
MT2716
MT6835
MT6858
MT6878
MT6879
MT6881
MT6886
MT6895
MT6896
MT6897
MT6899
MT6980
MT6982
MT6983
MT6985
MT6986
MT6779
MT6781
MT6785
Detailed vulnerability description
The vulnerability allows a local user to cause memory corruption.
The vulnerability exists due to out-of-bounds write in the modem when processing input. A local user can send crafted input to cause memory corruption.
How to mitigate CVE-2026-20458
Install security update from vendor's website.