cve-2026-80156

CRITICAL CVSS 9.4 cvelistv5
Description

Lantronix SLC8000 before firmware v9.7.0.5, EMG8500/EMG7500 before firmware v9.7.0.1, and all firmware versions of SLB882/SLCx-03/SLCx-02 contain a path traversal vulnerability in the web management portal upload endpoint that allows authenticated attackers to write arbitrary data to any location on the device's filesystem, leading to remote code execution. The upload filename validation strips backslash characters but does not subsequently check for forward slashes when a backslash is detected; by supplying a filename containing both characters an attacker writes outside the intended upload directory to any writable path. Attackers can use this vulnerability to achieve complete loss of confidentiality, integrity, and availability on the affected device and potentially impact downstream serial-connected devices.

Timeline
Published
2026-09-22 15:23 UTC
Last Modified
2026-09-23
CVSS Details
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
HIGH
Affected Products
  • LANTRONIX SLC8000
  • LANTRONIX EMG8500
  • LANTRONIX EMG7500
  • LANTRONIX SLB882
  • LANTRONIX SLCx-03
  • LANTRONIX SLCx-02
Weaknesses (CWE)
CWE-22
SSVC (CISA Stakeholder-Specific Vulnerability Categorization) CISA Coordinator v2.0.3
Exploitation
none
Automatable
no
Technical Impact
total
Decision timestamp
2026-09-23T15:42:01.037508Z

What is SSVC? — CISA's vulnerability-prioritisation framework using a decision tree rather than a single score.

References
Linked Vulnerabilities

No linked vulnerabilities found.

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