CVE-2026-91191High· 7.5▾ Twilight

The device's update mechanism includes conditions that allow unauthorized software packages to be accepted as authentic

▾ Twilight zone — High severity, or a signal on a lesser flaw

Depth score41/ 100 · Moderate

impact 41.3 · likelihood 0 · exploitation 0

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Proof of concept

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Published

Sep 29, 2026

Updated

Sep 29, 2026

CVSS

7.5

Vendor

Lantronix

Product

G520 Series

CWE

CWE-347

Depth score

41 · Moderate

EPSS

—

Platforms

—

Source

NVD

Vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

Lantronix CWE-347 #nvd #cve.org

Affected

g520_series 2.6.0.4R6 stable

Full technical detail▾

Overview

The device's update mechanism includes conditions that allow unauthorized software packages to be accepted as authentic. During the boot process, the stock done function disables signature verification in the OPKG configuration before restoring optional packages from a writable, unsigned feed. Separately, the publicly distributed SDK contains the production private key whose corresponding public key is trusted by both stable and beta firmware builds. Either issue undermines package authenticity, and together they allow an attacker to provide packages that appear valid to the system. Even if signature enforcement is restored, the exposed production key enables an attacker to generate signatures that the device will continue to trust. An attacker who can supply a malicious package may be able to execute arbitrary code with root privileges during installation.

Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

References

Related vulnerabilities

Connected by shared product, vendor, weakness, or advisory.

#nvd#cve.org