Physical code execution via exposed UART interface
Published Oct 5, 2026 · Updated Oct 5, 2026
Code execution in MERCUSYS AC12 V2 allows physically proximate attackers to run arbitrary code through the PCB's UART serial interface. The PCB-mounted UART interface is the reported entry point; the published CVE record does not explain its command path or access-control failure. Exploitation requires access to the router's circuit board, and the record does not establish a network-reachable attack path or an affected firmware build.
Summary
What happened
Code execution in MERCUSYS AC12 V2 allows physically proximate attackers to run arbitrary code through the PCB's UART serial interface. The PCB-mounted UART interface is the reported entry point; the published CVE record does not explain its command path or access-control failure. Exploitation requires access to the router's circuit board, and the record does not establish a network-reachable attack path or an affected firmware build.
The record
- CVE
- CVE-2026-78862
- Published
- Oct 5, 2026
- Updated
- Oct 5, 2026
- Vendor
- MERCUSYS
- Product
- AC12
- Classifications
- Unavailable
- Attack vector
- physical
- Privileges
- Unavailable
Timeline
How it unfolded
- Oct 5, 2026CVE publishedPublication date reported by the CVE source.
- Oct 5, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=n/a
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
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.
Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
No sourced classifications are available.
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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