CVE-2026-80155

CRITICALPre-NVD 10.010.0—
EchelonGraph scoreHIGH confidence

Score 10.0 from GitHub Security Advisory (severity: CRITICAL) published 2026-09-22. a secondary CVSS source baseline 10.0; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
10.0EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 2%CVSS: 10.0Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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 an authentication bypass vulnerability in the web management portal upload endpoint that allows unauthenticated attackers to read sensitive configuration files and upload files to arbitrary filesystem locations, leading to remote code execution. The web configuration server constructs the session cookie file path using snprintf with a fixed-size buffer; by supplying a cookie value of a specific length an attacker causes the path to truncate at the required delimiter and leverages path traversal to redirect authentication validation to an arbitrary on-disk file such as the local user database, bypassing all session checks. 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.

CVSS v3
10.0
EG Score
10.0(high)
EG Risk
61(Track)
EG Risk 61/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity100% × 45%
Exploitation2% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
2%
EPSS %ILE
74%
KEV
Not listed

Published

September 22, 2026

Last Modified

September 22, 2026

Advisory Details (5)

Auto-updated Sep 22, 2026
No patch confirmed yet.
generic

Lantronix Autonomous Out-of-Band Devices Unauthenticated Authentication Bypass via snprintf Path Truncation | Advisories | VulnCheck

https://www.vulncheck.com/advisories/lantronix-autonomous-out-of-band-devices-unauthenticated-authentication-bypass-via-snprintf-path-truncation
generic

ts.lantronix.com - /ftp/slc8000/9.7.0.5R2/

https://ts.lantronix.com/ftp/slc8000/9.7.0.5R2/
generic

ts.lantronix.com - /ftp/emg/EMG_8500/9.7.0.1R2/

https://ts.lantronix.com/ftp/emg/EMG_8500/9.7.0.1R2/
generic

ts.lantronix.com - /ftp/emg/EMG_7500/9.7.0.1R2/

https://ts.lantronix.com/ftp/emg/EMG_7500/9.7.0.1R2/
generic

REVRB-LANTERN: Security Research on Lantronix Autonomous Out-of-Band Devices | RE/VRb LLC

https://revrb.net/2026/09/21/revrb-lantern.html

Vendor Advisories for CVE-2026-80155(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 15× in last 7d / 15× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-09-24 03:52 UTCGHSA enrichment
  2. 2026-09-23 23:29 UTCGHSA enrichment
  3. 2026-09-23 19:06 UTCEG score recompute
  4. 2026-09-23 19:06 UTCGHSA enrichment
  5. 2026-09-23 17:54 UTCEPSS rescore
  6. 2026-09-23 14:02 UTCGHSA enrichment
  7. 2026-09-23 09:40 UTCGHSA enrichment
  8. 2026-09-23 05:18 UTCGHSA enrichment
  9. 2026-09-23 00:56 UTCGHSA enrichment
  10. 2026-09-22 20:33 UTCEG score recompute
  11. 2026-09-22 20:33 UTCGHSA enrichment
  12. 2026-09-22 16:19 UTCEG score recompute
  13. 2026-09-22 15:45 UTCEG score recompute
  14. 2026-09-22 15:30 UTCEG score recompute
  15. 2026-09-22 15:29 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-80155?
CVE-2026-80155 is a critical vulnerability published on September 22, 2026. 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 an authentication bypass vulnerability in the web management portal upload endpoint that allows unauthenticated attackers to read sensitive configuration…
When was CVE-2026-80155 disclosed?
CVE-2026-80155 was first published in the National Vulnerability Database on September 22, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-80155 actively exploited?
CVE-2026-80155 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 2% probability of exploitation in the next 30 days, which ranks it in the top 25.6% of all scored CVEs.
What is the CVSS score of CVE-2026-80155?
CVE-2026-80155 has a CVSS v3 base score of 10.0 (NVD).
How do I remediate CVE-2026-80155?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-80155, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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