MediaTek Modem Side-Channel Info Disclosure: Remote DoS via Rogue BS
CVE-2026-20578 Published on November 2, 2026

In Modem, there is a possible information disclosure due to side channel information disclosure. This could lead to remote denial of service, if a UE has connected to a rogue base station controlled by the attacker, with no additional execution privileges needed. User interaction is not needed for exploitation. Patch ID: MOLY01879164; Issue ID: MSV-9846.

NVD

Vulnerability Analysis

Attack Vector:
ADJACENT_NETWORK
Attack Complexity:
HIGH
Privileges Required:
NONE
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
NONE
Integrity Impact:
NONE
Availability Impact:
HIGH

Weakness Type

What is an Algorithm Downgrade Vulnerability?

A protocol or its implementation supports interaction between multiple actors and allows those actors to negotiate which algorithm should be used as a protection mechanism such as encryption or authentication, but it does not select the strongest algorithm that is available to both parties. When a security mechanism can be forced to downgrade to use a less secure algorithm, this can make it easier for attackers to compromise the software by exploiting weaker algorithm. The victim might not be aware that the less secure algorithm is being used. For example, if an attacker can force a communications channel to use cleartext instead of strongly-encrypted data, then the attacker could read the channel by sniffing, instead of going through extra effort of trying to decrypt the data using brute force techniques.

CVE-2026-20578 has been classified to as an Algorithm Downgrade vulnerability or weakness.


Affected Versions

MediaTek, Inc. MediaTek chipset: