RADIUS incorrect Vendor-Length in a Vendor-Specific attribute can cause a denial of service

radius-vendor-attribute-dos (8354) The risk level is classified as MediumMedium Risk


Multiple vendor implementations of the RADIUS (Remote Authentication Dial In User Service) Protocol are vulnerable to a denial of service attack caused improper validation of the Vendor-Specific Length attribute. A remote attacker can set the Vendor-Length of a Vendor-Specific attribute to value less than 2 to cause the RADIUS server or client to crash.


Denial of Service


Upgrade to the latest version of Cistron RADIUS (1.6.6 or later), available from the Cistron RADIUS Web site. See References.

For Red Hat Powertools 7.0 and 7.1:
Upgrade to the latest version of radiusd-cistron (1.6.6-2 or later), as listed in Red Hat Linux Errata Advisory RHSA-2002:030-08. See References.

For other distributions:
Contact your vendor for upgrade or patch information or refer to CERT Vulnerability Note VU#936683. See References.


Platforms Affected:

  • Cistron Cistron RADIUS 1.6.4
  • FreeRADIUS FreeRADIUS prior to 0.4
  • GNU Radius 0.92.1
  • GNU Radius 0.93
  • GNU Radius 0.94
  • GNU Radius 0.95
  • IC ICRadius
  • RedHat Linux 7
  • RedHat Linux 7.1
  • RedHat Linux 7.2
  • RedHat Linux 7.3
  • RedHat Linux Powertools 7.0
  • RedHat Linux Powertools 7.1
  • XTRADIUS XTRADIUS prior to 1.2.1


Dec 18, 2001

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