Modem crash via unchecked out-of-bounds write
Published Feb 2, 2026 · Updated Feb 2, 2026
An out-of-bounds write in MediaTek Modem NR15 allows physically proximate attackers controlling a rogue base station to crash the modem. The modem fails to validate an undisclosed input before writing outside the intended buffer; MediaTek has not identified the affected parser or field. Exploitation requires the user equipment to connect to the attacker-controlled base station, needs no privileges or user interaction, and interrupts modem service.
Summary
What happened
An out-of-bounds write in MediaTek Modem NR15 allows physically proximate attackers controlling a rogue base station to crash the modem. The modem fails to validate an undisclosed input before writing outside the intended buffer; MediaTek has not identified the affected parser or field. Exploitation requires the user equipment to connect to the attacker-controlled base station, needs no privileges or user interaction, and interrupts modem service.
The record
- CVE
- CVE-2026-20402
- Published
- Feb 2, 2026
- Updated
- Feb 2, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-787, 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
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo