Path Traversal in Lantronix Emg7500
CVE-2026-80156
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.
Vulnerability class: Path Traversal (Directory Traversal)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- revrb.net/2026/09/21/revrb-lantern.html (technical-description)
- ts.lantronix.com/ftp/slc8000/9.7.0.5R2/ (patch)
- ts.lantronix.com/ftp/emg/EMG_8500/9.7.0.1R2/ (patch)
- ts.lantronix.com/ftp/emg/EMG_7500/9.7.0.1R2/ (patch)
- www.vulncheck.com/advisories/lantronix-autonomous-out-of-band-devices-arbitrary… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-80156?
- CVE-2026-80156 is a critical-severity vulnerability in Lantronix Emg7500, classified under Path Traversal. CVSS score: 9.1/10. Published 2026-09-22.
- How severe is CVE-2026-80156?
- Critical severity. CVSS v3 base score is 9.1 out of 10.