CVE-2017-12240 : What You Need to Know
Learn about CVE-2017-12240, a critical vulnerability in Cisco IOS and IOS XE software versions 12.2 through 15.6. Attackers can exploit the DHCP relay subsystem flaw to execute arbitrary code, gain system control, and cause denial of service.
Cisco IOS versions 12.2 through 15.6 and Cisco IOS XE Software are affected by a vulnerability in the DHCP relay subsystem that allows unauthorized remote attackers to execute arbitrary code, gain full control of the system, and cause denial of service by triggering system reloads.
Understanding CVE-2017-12240
This CVE identifier pertains to a critical vulnerability in Cisco networking software that can be exploited by attackers to compromise affected systems.
What is CVE-2017-12240?
The vulnerability in Cisco IOS and IOS XE software versions 12.2 through 15.6 lies in the DHCP relay subsystem, enabling attackers to execute arbitrary code, take control of the system, and induce denial of service situations.
The Impact of CVE-2017-12240
Exploitation of this vulnerability can lead to severe consequences:
- Unauthorized execution of arbitrary code
- Complete compromise of the affected system
- Triggering system reloads, causing denial of service
Technical Details of CVE-2017-12240
This section delves into the technical aspects of the vulnerability.
Vulnerability Description
The flaw arises from a buffer overflow issue within the DHCP relay subsystem of the affected software, allowing attackers to exploit it by sending manipulated DHCPv4 packets.
Affected Systems and Versions
- Product: Cisco IOS and IOS XE
- Versions: Cisco IOS and IOS XE
Exploitation Mechanism
Attackers can exploit the vulnerability by sending crafted DHCPv4 packets to the targeted system, enabling them to execute arbitrary code, gain system control, or induce system reloads.
Mitigation and Prevention
To address CVE-2017-12240, follow these mitigation strategies:
Immediate Steps to Take
- Apply vendor-supplied patches promptly
- Implement network segmentation to limit the impact of potential attacks
- Monitor network traffic for signs of exploitation
Long-Term Security Practices
- Regularly update and patch all software and firmware
- Conduct security assessments and penetration testing
- Educate users and administrators on best security practices
Patching and Updates
- Cisco has released patches to address this vulnerability
- Regularly check for updates and apply them to ensure system security