MediaTek Modem OOB Write (CVE-2026-20433)
CVE-2026-20433 Published on April 7, 2026
In Modem, there is a possible out of bounds write due to a missing bounds check. This could lead to remote escalation of privilege, if a UE has connected to a rogue base station controlled by the attacker, with no additional execution privileges needed. User interaction is needed for exploitation. Patch ID: MOLY01088681; Issue ID: MSV-4460.
Vulnerability Analysis
Weakness Type
What is a Memory Corruption Vulnerability?
The software writes data past the end, or before the beginning, of the intended buffer. Typically, this can result in corruption of data, a crash, or code execution. The software may modify an index or perform pointer arithmetic that references a memory location that is outside of the boundaries of the buffer. A subsequent write operation then produces undefined or unexpected results.
CVE-2026-20433 has been classified to as a Memory Corruption vulnerability or weakness.
Affected Versions
MediaTek, Inc. MediaTek chipset:- Version MT2735 is affected.
- Version MT2737 is affected.
- Version MT6813 is affected.
- Version MT6833 is affected.
- Version MT6833P is affected.
- Version MT6835 is affected.
- Version MT6835T is affected.
- Version MT6853 is affected.
- Version MT6853T is affected.
- Version MT6855 is affected.
- Version MT6855T is affected.
- Version MT6873 is affected.
- Version MT6875 is affected.
- Version MT6875T is affected.
- Version MT6877 is affected.
- Version MT6877T is affected.
- Version MT6877TT is affected.
- Version MT6878 is affected.
- Version MT6878M is affected.
- Version MT6879 is affected.
- Version MT6880 is affected.
- Version MT6883 is affected.
- Version MT6885 is affected.
- Version MT6886 is affected.
- Version MT6889 is affected.
- Version MT6890 is affected.
- Version MT6891 is affected.
- Version MT6893 is affected.
- Version MT6895 is affected.
- Version MT6895TT is affected.
- Version MT6896 is affected.
- Version MT6897 is affected.
- Version MT6899 is affected.
- Version MT6980 is affected.
- Version MT6980D is affected.
- Version MT6983 is affected.
- Version MT6983T is affected.
- Version MT6985 is affected.
- Version MT6985T is affected.
- Version MT6989 is affected.
- Version MT6989T is affected.
- Version MT6990 is affected.
- Version MT6991 is affected.
- Version MT8668 is affected.
- Version MT8673 is affected.
- Version MT8675 is affected.
- Version MT8676 is affected.
- Version MT8678 is affected.
- Version MT8755 is affected.
- Version MT8771 is affected.
- Version MT8775 is affected.
- Version MT8791 is affected.
- Version MT8791T is affected.
- Version MT8792 is affected.
- Version MT8793 is affected.
- Version MT8795T is affected.
- Version MT8797 is affected.
- Version MT8798 is affected.
- Version MT8863 is affected.
- Version MT8873 is affected.
- Version MT8883 is affected.
- Version MT8893 is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.