Adjacent denial of service via modem out-of-bounds read
Published Feb 2, 2026 · Updated Feb 2, 2026
Out-of-bounds read in the MediaTek chipset modem allows physically proximate attackers to crash the system through a rogue base station. The modem reads beyond an intended memory boundary and handles the resulting error incorrectly; MediaTek has not disclosed the affected routine or message field. Exploitation requires the user equipment to connect to an attacker-controlled base station, needs no privileges or user interaction, and crashes the system without reported code execution or data access.
Summary
What happened
Out-of-bounds read in the MediaTek chipset modem allows physically proximate attackers to crash the system through a rogue base station. The modem reads beyond an intended memory boundary and handles the resulting error incorrectly; MediaTek has not disclosed the affected routine or message field. Exploitation requires the user equipment to connect to an attacker-controlled base station, needs no privileges or user interaction, and crashes the system without reported code execution or data access.
The record
- CVE
- CVE-2026-20420
- Published
- Feb 2, 2026
- Updated
- Feb 2, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-125, T1499
- Attack vector
- adjacent
- Privileges
- unauthenticated
Timeline
How it unfolded
- Feb 2, 2026CVE publishedPublication date reported by the CVE source.
- Feb 2, 2026Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
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Attacks
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Public exploit references
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Technologies
Your stack
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Your stack
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