CVE-2026-91191 Lantronix G520 Series Cellular Gateway Improper Verification of Cryptographic Signature
Attackers can execute arbitrary code with root privileges by exploiting a hardcoded private key and disabled signature verification in the update mechanism.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-91191?
CVE-2026-91191 is a high-severity vulnerability in Lantronix G520 Series, published on 29 Sep 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
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.
Weakness: CWE-347
Which versions are affected by CVE-2026-91191?
How do I fix CVE-2026-91191?
No fix has been published for CVE-2026-91191 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-91191 being exploited?
There is no known exploitation of CVE-2026-91191 in the wild and no public exploit code.
Sources
Also known as GHSA-q7r9-65j5-94xj.