What is CVE-2026-39453?

CVE-2026-39453 is a high-severity vulnerability in Red Lion Controls 700 Series, classified under Reachable Assertion. CVSS score: 8.3/10. Published 2026-10-09.

How severe is CVE-2026-39453?

High severity. CVSS v3 base score is 8.3 out of 10.

Vulnerability in Red Lion Controls 700 Series

CVE-2026-39453

Navigating to a certain URL on the switch’s web server causes the switch to reboot. This can be automated using a tool like curl to create DoS conditions where the switch constantly reboots.

Published 2026-10-09 · last modified 2026-10-09.

CVSS v3 metric

CVSS v3 base score 8.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Red Lion Controls 700 Series

Weakness classification (CWE)

CWE-617 — Reachable Assertion

References

www.hms-networks.com/
www.hms-networks.com/cybersecurity
www.cisa.gov/news-events/ics-advisories/icsa-26-281-01
github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-281-01.js…

Frequently asked questions

What is CVE-2026-39453?: CVE-2026-39453 is a high-severity vulnerability in Red Lion Controls 700 Series, classified under Reachable Assertion. CVSS score: 8.3/10. Published 2026-10-09.
How severe is CVE-2026-39453?: High severity. CVSS v3 base score is 8.3 out of 10.