Is CVE-2026-91191 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-91191 being exploited in the wild.

How severe is CVE-2026-91191?

High severity, with a CVSS score of 7.5, published 29 September 2026.

Which products and versions are affected?

Lantronix G520 Series Cellular Gateway 2.6.0.4R6_stable.

Is there a fix for CVE-2026-91191?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-91191 attacked?

It is attacked over the network, in a network appliance.

Am I affected by CVE-2026-91191?

Check whether you run Lantronix G520 Series Cellular Gateway at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-91191: Lantronix G520 Series Cellular Gateway signature verification and XSS

CVE-2026-91191 · Severity: high · CVSS 7.5 · Published 2026-09-29

Lantronix G520 Series Cellular Gateways, which provide wireless connectivity for critical infrastructure in transportation, energy, and water systems, contain two security vulnerabilities. An attacker could exploit improper cryptographic signature verification to replace device software, and use cross-site scripting to execute arbitrary code with root privileges. These flaws could lead to complete device compromise and disruption of critical operations.

Vendors: Lantronix.

Quick answers

Is CVE-2026-91191 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-91191 being exploited in the wild.
How severe is CVE-2026-91191?: High severity, with a CVSS score of 7.5, published 29 September 2026.
Which products and versions are affected?: Lantronix G520 Series Cellular Gateway 2.6.0.4R6_stable.
Is there a fix for CVE-2026-91191?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-91191 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-91191?: Check whether you run Lantronix G520 Series Cellular Gateway at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The vulnerabilities involve improper neutralization of input during web page generation (cross-site scripting) and improper verification of cryptographic signatures, allowing an attacker to bypass authentication controls and execute arbitrary code with root privileges. The affected component is the G520 Series firmware; attack vectors include network access to the web interface and the software update mechanism. No patch information is currently available.

Affected products

Lantronix G520 Series Cellular Gateway 2.6.0.4R6_stable

Identifiers

CVE-2026-91191
CVE-2026-84409

Timeline

2026-09-29: disclosed

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