CVE-2026-20599: MediaTek Modem privilege escalation due to missing permission check

CVE-2026-20599 · Severity: info · Published 2026-11-02

MediaTek Modem chipsets contain a missing permission check that allows escalation of privilege to a higher security level. An attacker who has already compromised a system with user-level privileges could exploit this flaw to gain System privilege without needing to trick a user, potentially gaining complete control over the device.

Technologies: MediaTek Modem. Vendors: MediaTek.

Quick answers

Is CVE-2026-20599 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-20599 being exploited in the wild.
How severe is CVE-2026-20599?
Informational severity, published 2 November 2026.
Which products and versions are affected?
MediaTek Modem.
Is there a fix for CVE-2026-20599?
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-2026-20599 attacked?
It is attacked with local access, in device firmware.
Am I affected by CVE-2026-20599?
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

The vulnerability is a missing permission check in MediaTek Modem that enables privilege escalation. Exploitation requires local access with already-elevated System privilege; no user interaction is needed. A successful exploit grants the attacker higher privilege levels within the modem firmware.

Affected products

  • MediaTek Modem

Timeline

  • 2026-11-02: disclosed

References

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