Gandalf_The_Grey
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- Apr 24, 2016
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Zyxel is warning that a bad security signature update is causing critical errors for USG FLEX or ATP Series firewalls, including putting the device into a boot loop.
"We've found an issue affecting a few devices that may cause reboot loops, ZySH daemon failures, or login access problems," warns a new Zyxel advisory.
"The system LED may also flash. Please note this is not related to a CVE or security issue."
Zyxel says the issues are caused by a failure in an Application Signature Update for its cybersecurity features that was pushed out on 1/24 through 1/25 at night.
As first reported by Born City, the only way to fix the issue is to have physical access to the firewall and to connect to the console via an RS232 serial cable.
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Zyxel warns of bad signature update causing firewall boot loops
Zyxel is warning that a bad security signature update is causing critical errors for USG FLEX or ATP Series firewalls, including putting the device into a boot loop.