Versions affected: 4.0.x and higher, including all EOL versions back to 4.0, 4.1-ESV, and 4.2.x
A bug exists which allows an attacker who is able
to send DHCP Request packets, either directly or through a relay, to
remotely crash an ISC DHCP server if that server is configured to
evaluate expressions using a regular expression (i.e. uses the "~=" or
"~~" comparison operators.)
Further details are being withheld to allow administrators of
affected systems time to patch. You are potentially vulnerable if you
use regular expression comparison operators in your dhcpd.conf.
CVSS Score: 6.1
CVSS Equation: AV:
For more information on the Common Vulnerability Scoring System and to obtain your specific environmental score please visit: http://nvd.nist.gov/cvss.cfm?calculator&adv&version=2&vector=(tbd)
This bug cannot be triggered if you are not using regular expressions in your configuration file.
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