CVE-2026-80156

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.

Overview

State: PUBLISHED
Assigner (CNA): VulnCheck
CVSS severity: CRITICAL
CVSS score: 9.4 / 10
CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
Effective score: 9.4 / 10 CRITICAL source: CNA overview
CWE(s): CWE-22
Reserved: 2026-08-25
Published: 2026-09-22 15:23 UTC
Last updated: 2026-09-22 15:23 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/80xxx/CVE-2026-80156.json
Linked Threat: CVE-2026-80156 — Lantronix Autonomous Out-of-Band Devices Arbitrary File Write via Upload Filename Validation Bypass

NVD triage scoring NVD CVE 2.0

Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.

NVD published: 2026-09-22 16:18:02 UTC
NVD last modified: 2026-09-22 20:25:55 UTC
NVD CVSS v3.1: 9.1 / 10 CRITICAL source: disclosure@vulncheck.com
NVD CVSS vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Exploitability subscore: 2.3 / 10
Impact subscore: 6.0 / 10

European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2026-84523
Assigner: VulnCheck
Published: Sep 22, 2026, 3:23:24 PM
Updated: Sep 22, 2026, 3:23:24 PM
EUVD base score (CVSS 4.0): 9.4 / 10
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
EUVD-reported EPSS: 0.0000
Vendors: Lantronix
Products: EMG7500 (0 <9.7.0.1)

SLCx-03 (*)

SLCx-02 (*)

SLC8000 (0 <9.7.0.5)

SLB882 (*)

EMG8500 (0 <9.7.0.1)
Aliases: GHSA-hmch-26g2-q5qx

ENISA 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.

EUVD references (5)

Affected products (6)

Vendor	Product	Versions	Platforms
LANTRONIX	SLC8000	`0` (affected)	—
LANTRONIX	EMG8500	`0` (affected)	—
LANTRONIX	EMG7500	`0` (affected)	—
LANTRONIX	SLB882	`*` (affected)	—
LANTRONIX	SLCx-03	`*` (affected)	—
LANTRONIX	SLCx-02	`*` (affected)	—

Vendor references (5)

References embedded in the original CVE record by the assigning CNA.

Researcher Disclosure technical-description
SLC8000 Firmware patch
EMG8500 Firmware patch
EMG7500 Firmware patch
https://www.vulncheck.com/advisories/lantronix-autonomous-out-of-band-devices-arbitrary-file-write-via-upload-filename-validation-bypass third-party-advisory

Web references (0)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

No web references attached yet.

NVD-tagged references (5)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

https://revrb.net/2026/09/21/revrb-lantern.html disclosure@vulncheck.com
https://ts.lantronix.com/ftp/emg/EMG_7500/9.7.0.1R2/ disclosure@vulncheck.com
https://ts.lantronix.com/ftp/emg/EMG_8500/9.7.0.1R2/ disclosure@vulncheck.com
https://ts.lantronix.com/ftp/slc8000/9.7.0.5R2/ disclosure@vulncheck.com
https://www.vulncheck.com/advisories/lantronix-autonomous-out-of-band-devices-arbitrary-file-write-via-upload-filename-validation-bypass disclosure@vulncheck.com

Remediations (10)

Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.

Microsoft Defender Patch Bypass: High Severity Zero-Day Privilege ...

web:arcticwolf.com

Validate Group Policy and registry settings for Defender to ensure real-time protection, automatic remediation , and exclusion policies are secured. Temporary Workarounds Block Vulnerable Apps: Use Microsoft Defender Vulnerability Management to block or warn against execution of affected binaries for systems pending a patch .

2026-09-23 15:14 UTC
CVE-2026-80156 - Lantronix Autonomous Out-of-Band Devices Arbitrary ...

web:cvefeed.io

The following list is the news that have been mention CVE-2026-80156 vulnerability anywhere in the article. Results are limited to the first 20 news articles due to potential performance issues. The following table lists the changes that have been made to the CVE-2026-80156 vulnerability over time.

2026-09-23 15:14 UTC
CVE-2026-80156: Lantronix Path Traversal (CVSS 9.1) | CVETodo

web:cvetodo.com

CVE-2026-80156 is a Path Traversal vulnerability in Lantronix SLC8000, EMG8500, EMG7500. See exploitation status, patch guidance, and technical details.

2026-09-23 15:14 UTC
Defender Zero-Day CVE-2026-50656 Under Active Exploit, No Patch

web:dailysecurityreview.com

Microsoft confirmed CVE - 2026 -50656, a zero-day in the Defender Malware Protection Engine allowing SYSTEM-level privilege escalation, is under active exploitation with no patch currently available.

2026-09-23 15:14 UTC
Security Update Guide - Microsoft Security Response Center

web:msrc.microsoft.com

Security Update Guide - Microsoft Security Response Center

2026-09-23 15:14 UTC
Microsoft Patch Tracker (September 2026): Exploit-Ranked | Senserva

web:senserva.com

Every Microsoft security patch (KB) and the CVEs it fixes, with severity, CVSS, and CISA KEV status. Cross-linked to the CVE reference.

2026-09-23 15:14 UTC
CVE-2026-50656 ShieldBreak Claims Defender Fix Bypass — Megathread

web:windowsforum.com

ShieldBreak, a newly published proof of concept from the researcher known as Nightmare Eclipse, claims to bypass Microsoft's July fix for the Microsoft Defender privilege-escalation flaw CVE - 2026 -50656, better known as RoguePlanet.

2026-09-23 15:14 UTC
Microsoft August 2026 Patch Tuesday fixes 400 flaws, 3 zero-days

web:www.bleepingcomputer.com

Today is Microsoft's August 2026 Patch Tuesday, and with it comes security updates for a massive 400 flaws, including one actively exploited and two publicly disclosed zero-day vulnerabilities.

2026-09-23 15:14 UTC
July Patch RoguePlanet Tuesday Kills Windows Kerberos RC4 Rollback ...

web:www.techtimes.com

July 2026 Patch Tuesday permanently removes the Kerberos RC4 rollback registry key on July 14, leaving service accounts with RC4-only material unable to authenticate. Administrators must also ...

2026-09-23 15:14 UTC
July 2026 Patch Tuesday: Largest Patch Tuesday 569 CVEs - Tenable

web:www.tenable.com

Microsoft patched 569 CVEs in July 2026 , the largest Patch Tuesday release in its history. 56 critical CVEs patched including three zero-day vulnerabilities.

2026-09-23 15:14 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-80156.json.

{
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        {
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          "product": "SLC8000",
          "vendor": "LANTRONIX",
          "versions": [
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              "version": "0",
              "versionType": "custom"
            }
          ]
        },
        {
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          "product": "EMG8500",
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        },
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              "status": "affected",
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          "value": "RE/VRb"
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      ],
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        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 9.4,
            "baseSeverity": "CRITICAL",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "HIGH",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "HIGH",
            "subConfidentialityImpact": "HIGH",
            "subIntegrityImpact": "HIGH",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
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            "vulnerabilityResponseEffort": "NOT_DEFINED"
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            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "HIGH",
            "scope": "CHANGED",
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            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H",
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      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-22",
              "description": "Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-22T15:23:24.784Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "name": "Researcher Disclosure",
          "tags": [
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        },
        {
          "name": "SLC8000 Firmware",
          "tags": [
            "patch"
          ],
          "url": "https://ts.lantronix.com/ftp/slc8000/9.7.0.5R2/"
        },
        {
          "name": "EMG8500 Firmware",
          "tags": [
            "patch"
          ],
          "url": "https://ts.lantronix.com/ftp/emg/EMG_8500/9.7.0.1R2/"
        },
        {
          "name": "EMG7500 Firmware",
          "tags": [
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          ],
          "url": "https://ts.lantronix.com/ftp/emg/EMG_7500/9.7.0.1R2/"
        },
        {
          "tags": [
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          ],
          "url": "https://www.vulncheck.com/advisories/lantronix-autonomous-out-of-band-devices-arbitrary-file-write-via-upload-filename-validation-bypass"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "Lantronix Autonomous Out-of-Band Devices Arbitrary File Write via Upload Filename Validation Bypass",
      "x_generator": {
        "engine": "vulncheck"
      }
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  "cveMetadata": {
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    "assignerShortName": "VulnCheck",
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    "datePublished": "2026-09-22T15:23:24.784Z",
    "dateReserved": "2026-08-25T20:43:54.262Z",
    "dateUpdated": "2026-09-22T15:23:24.784Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}