Is CVE-2026-20431 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-20431 being exploited in the wild.

How severe is CVE-2026-20431?

Medium severity, with a CVSS score of 6.5, published 7 April 2026.

Which products and versions are affected?

MediaTek MT6813; MediaTek MT6815; MediaTek MT6835; MediaTek MT6878; and 15 more.

Is there a fix for CVE-2026-20431?

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-2026-20431 attacked?

It is attacked from the adjacent network, in device firmware.

Am I affected by CVE-2026-20431?

Check whether anything you run is named in the advisory. 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.

CVE-2026-20431: MediaTek Chipset denial of service in Modem

CVE-2026-20431 · Severity: medium · CVSS 6.5 · Published 2026-04-07

A vulnerability in certain MediaTek chipsets could allow an attacker to crash a mobile device's modem, leading to a loss of cellular connectivity. This occurs when a device connects to a malicious base station (rogue cell tower) controlled by the attacker. An exploit would result in a denial of service, preventing the user from making calls or using mobile data until the system is recovered.

Quick answers

Is CVE-2026-20431 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-20431 being exploited in the wild.
How severe is CVE-2026-20431?: Medium severity, with a CVSS score of 6.5, published 7 April 2026.
Which products and versions are affected?: MediaTek MT6813; MediaTek MT6815; MediaTek MT6835; MediaTek MT6878; and 15 more.
Is there a fix for CVE-2026-20431?: 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-2026-20431 attacked?: It is attacked from the adjacent network, in device firmware.
Am I affected by CVE-2026-20431?: Check whether anything you run is named in the advisory. 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

A logic error in the MediaTek modem firmware (CWE-770) leads to a system crash when the User Equipment (UE) interacts with a rogue base station. The vulnerability is exploitable via an adjacent network vector without requiring authentication or user interaction. An attacker in physical proximity can deploy a rogue base station to trigger a remote denial of service (DoS) on affected devices. MediaTek has released Patch ID MOLY01106496 to address this issue across multiple chipset models including MT68xx, MT69xx, and MT8xxx series.

Affected products

MediaTek MT6813
MediaTek MT6815
MediaTek MT6835
MediaTek MT6878
MediaTek MT6897
MediaTek MT6899
MediaTek MT6986
MediaTek MT6991
MediaTek MT6993
MediaTek MT8668
MediaTek MT8676
MediaTek MT8678
MediaTek MT8755
MediaTek MT8775
MediaTek MT8792
MediaTek MT8793
MediaTek MT8863
MediaTek MT8873
MediaTek MT8883

Timeline

2026-04-07: advisory: MediaTek published the security bulletin
2026-04-07: disclosed: CVE published to NVD

References

https://corp.mediatek.com/product-security-bulletin/April-2026

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