CVE-2026-20547 MediaTek, Inc. CVE debrief

Who should care

Defenders responsible for systems using Modem should assess exposure and prioritize patching or mitigating this vulnerability. The vulnerability could lead to remote escalation of privilege if a UE has connected to a rogue base station controlled by the attacker. Defenders should verify system exposure and prioritize patching or mitigating this vulnerability.

Why it matters

Defenders should prioritize patching or mitigating CVE-2026-20547, especially for systems exposed to rogue base stations, as it could lead to remote escalation of privilege.

• Remote escalation of privilege
• Potential for unauthorized access
• Need for patching or mitigation
• Verification of system exposure

Technical summary

A possible out of bounds write due to a missing bounds check was found in Modem. 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. The vulnerability affects systems using Modem and defenders should assess exposure and prioritize patching or mitigating this vulnerability. The CVE record and NVD entry provide limited information about the vulnerability, and further investigation is needed to determine the affected products and versions.

Defensive priority

Defenders should prioritize patching or mitigating this vulnerability, especially for systems exposed to rogue base stations.

Recommended defensive actions

• Patch or mitigate the vulnerability
• Monitor for rogue base stations
• Verify system exposure
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and NVD entry provide limited information about the vulnerability. Further investigation is needed to determine the affected products and versions. The vulnerability could lead to remote escalation of privilege if a UE has connected to a rogue base station controlled by the attacker. Defenders should verify system exposure and prioritize patching or mitigating this vulnerability.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.