CVE-2024-20266
MediumWhat is CVE-2024-20266?
A vulnerability in the DHCP version 4 (DHCPv4) server feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to trigger a crash of the dhcpd process, resulting in a denial of service (DoS) condition. This vulnerability exists because certain DHCPv4 messages are improperly validated when they are processed by an affected device. An attacker could exploit this vulnerability by sending a malformed DHCPv4 message to an affected device. A successful exploit could allow the attacker to cause a crash of the dhcpd process. While the dhcpd process is restarting, which may take approximately two minutes, DHCPv4 server services are unavailable on the affected device. This could temporarily prevent network access to clients that join the network during that time period and rely on the DHCPv4 server of the affected device. Notes: Only the dhcpd process crashes and eventually restarts automatically. The router does not reload. This vulnerability only applies to DHCPv4. DHCP version 6 (DHCPv6) is not affected.
CVSS Vector Breakdown
CVSS 3.1Exploitable remotely over the network without requiring access to the local system.
No special conditions required. Exploit can be performed reliably and repeatedly.
No authentication required. Any anonymous user can exploit this vulnerability.
No user interaction required. Exploit runs without any victim action.
Exploiting the vulnerability only affects the vulnerable component itself.
No confidentiality impact. Sensitive data is not exposed.
No integrity impact. Data cannot be modified.
Reduced performance or intermittent outages, but service remains available.
Known Affected Devices
FAQ
CVE-2024-20266 has a CVSS score of 5.3/10, rated as Medium. Review the affected products list and apply vendor patches.
CVSS (Common Vulnerability Scoring System) rates vulnerability severity from 0.0 to 10.0. CVE-2024-20266 scores 5.3/10 (Medium). Scores 9.0–10.0 are Critical, 7.0–8.9 are High, 4.0–6.9 are Medium, and below 4.0 are Low.
The list of devices confirmed to be affected by CVE-2024-20266 is shown in the "Affected Devices" section above. Check your firmware version against the vendor security advisory and apply the latest patch.
Apply the latest firmware or software update from the vendor. Check the References section above for official advisories and patch notes. If no patch is available, consider disabling the affected feature or isolating the device from untrusted networks.