CVE-2026-91191: Lantronix G520 Series · CWE-347
Affects Lantronix G520 SeriesSource CVE Database V5
Not known to be exploited · CVSS 7.5 High.
Data as of 12 Nov 2026, 23:25 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 12% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 29 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LantronixG520 Series | Affected
| Fixed in– |
AI-suggested
Until a patch is available, restrict access to the update mechanism and avoid using unsigned or untrusted package feeds.
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.
References
- ltrxdev.atlassian.net/wiki/spaces/LTRXTS/pages/1889828865/Latest+firmware+for+the+G520+Series+G526+G526RP+G527+G528 (opens in a new tab)
- lantronix.com/technical-support/security-updates/vulnerability-disclosure-policy/vulnerability-library/ (opens in a new tab)
- cisa.gov/news-events/ics-advisories/icsa-26-272-01 (opens in a new tab)
- github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-272-01.json (opens in a new tab)