CVE-2026-18685
Remote command injection in GL.iNet GL-MT3000 router firmware set_upgrade.
Is CVE-2026-18685 being exploited?
Not confirmed. CVE-2026-18685 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 2.0% probability of exploitation in the next 30 days.
How severe is CVE-2026-18685?
CVE-2026-18685 is rated High with a CVSS score of 8.9. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-18685?
Not known from our data. No patch reference has been recorded for CVE-2026-18685, which is not the same as no patch existing — a fix may have shipped without a tagged reference, or after this record was written. The vendor advisory is the only authority on whether a fix exists, and mitigations may be available regardless.
What does CVE-2026-18685 affect?
CVE-2026-18685 affects GL.iNet GL-MT3000 (firmware <= 4.4.5), modem.so /cgi-bin/glc set_upgrade. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-18685?
Isolate devices, disable remote admin, apply vendor firmware patch when released.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote command injection via /cgi-bin/glc set_upgrade enabling remote code execution, full device compromise, and network pivoting.
Immediate action required
- affected4.4.0
- affected4.4.1
- affected4.4.2
- affected4.4.3
- affected4.4.4
- affected4.4.5
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.