Cisco Small Business Switches Face Global DNS Crash Outage
ID: a4fab25a-b357-508d-b7d9-fff3d777e719
STIX ID: report--a4fab25a-b357-508d-b7d9-fff3d777e719
Feed Name: cybersecurityNews.com
A widespread failure on January 8, 2026 caused Cisco small-business switches (CBS250, C1200, CBS350, SG350, SG550X and related Catalyst lines) to crash and reboot repeatedly due to fatal DNS client errors when DNS lookups (including to default SNTP/time servers) failed; affected firmware versions include 4.1.7.17, 4.1.3.36, and 4.1.7.24. Administrators stabilized devices by disabling DNS or removing default SNTP servers, and Cisco acknowledged customer impacts but had not released a public advisory or patch at the time of reporting.
Your team is not currently subscribed to this feed. You must subscribe to it in order to see this post.