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8.6 High Exploited

CVE-2018-0173 Cisco IOS and IOS XE Software Improper Input Validation Vulnerability

Active exploitation observed

· CISA KEV catalogue
Required action Apply updates per vendor instructions.
Ransomware campaigns Not observed so far
Weakness CWE-20

Description

A vulnerability in the Cisco IOS Software and Cisco IOS XE Software function that restores encapsulated option 82 information in DHCP Version 4 (DHCPv4) packets could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a Relay Reply denial of service (DoS) condition. The vulnerability exists because the affected software performs incomplete input validation of encapsulated option 82 information that it receives in DHCPOFFER messages from DHCPv4 servers. An attacker could exploit this vulnerability by sending a crafted DHCPv4 packet to an affected device, which the device would then forward to a DHCPv4 server. When the affected software processes the option 82 information that is encapsulated in the response from the server, an error could occur. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Cisco Bug IDs: CSCvg62754.

Affected products and versions

Product Affected versions Fixed in
Cisco IOS and IOS XE Versions not published

References

Timeline

  1. Published
  2. Added to the KEV catalogue
  3. Last modified
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