cbcvebase.
CVE-2018-0174
published 2018-03-28

CVE-2018-0174: A vulnerability in the DHCP option 82 encapsulation functionality of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote…

PriorityP279high8.6CVSS 3.1
AVNACLPRNUINSCCNINAH
KEVITW
CISA Known Exploited Vulnerabilitydue 2022-03-17
Exploited in the wild
EPSS
7.76%
94.0th percentile
A vulnerability in the DHCP option 82 encapsulation functionality of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability exists because the affected software performs incomplete input validation of option 82 information that it receives in DHCP Version 4 (DHCPv4) packets from DHCP relay agents. An attacker could exploit this vulnerability by sending a crafted DHCPv4 packet to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Cisco Bug IDs: CSCuh91645.

Affected

7 ranges
VendorProductVersion rangeFixed in
ciscoios<= 15.2\(4a\)ea5
ciscoios<= 15.2\(6\)e0a
ciscoios
ciscoios_and_ios_xe
ciscoios_xe<= 15.2\(4a\)ea5
ciscoios_xe<= 15.2\(6\)e0a
ciscoios_xe

Detection & IOCsextracted from sources · hover to see the quote

  • Trigger condition: attacker sends a crafted DHCPv4 packet where the client-provided option 82 causes pEndOfEncapsulatedOpt82 to exceed pEndOfMsg, resulting in a very large memmove and access violation (device reload/DoS)
  • Target protocol/feature: DHCP option 82 encapsulation in DHCPv4 relay agent on Cisco IOS and IOS XE; monitor for crafted DHCPv4 packets containing malformed option 82 data sent to devices acting as DHCP relay agents
  • Cisco Bug ID CSCuh91645 can be used to cross-reference affected software versions and patch status in Cisco's security tooling
  • ·Vulnerability is only exploitable on devices with DHCP relay agent functionality enabled and configured to process option 82 encapsulation; devices not acting as DHCP relay agents are not affected
  • ·No workarounds are available; only vendor software updates address this vulnerability

CVSS provenance

nvdv3.18.6HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
nvdv2.07.8HIGHAV:N/AC:L/Au:N/C:N/I:N/A:C
vulncheck8.6HIGH
cisa8.6HIGH
vendor_cisco8.6HIGH
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