CVE-2026-20596: MediaTek Modem out-of-bounds read in input validation

CVE-2026-20596 · Severity: info · Published 2026-11-02

A flaw in MediaTek modem firmware can be triggered when a device connects to a malicious base station, causing the modem to read memory outside its intended bounds. An attacker controlling a rogue cellular base station can exploit this to crash modems in nearby devices, disrupting mobile connectivity for smartphones and IoT devices.

Technologies: MediaTek Modem. Vendors: MediaTek.

Quick answers

Is CVE-2026-20596 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-20596 being exploited in the wild.
How severe is CVE-2026-20596?
Informational severity, published 2 November 2026.
Which products and versions are affected?
MediaTek Modem.
Is there a fix for CVE-2026-20596?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-20596 attacked?
It is attacked from the adjacent network or over the network, in device firmware.
Am I affected by CVE-2026-20596?
Check whether you run MediaTek Modem. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

An out-of-bounds read vulnerability in MediaTek modem firmware results from improper input validation of cellular network signaling data. Attack vector is network-adjacent (requires a rogue base station in range); exploitation requires no authentication or user interaction and affects any connected device. The vulnerability leads to denial of service through memory corruption.

Affected products

  • MediaTek Modem

Timeline

  • 2026-11-02: disclosed

References

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