CVE-2017-12240

Cisco IOS and IOS XE Software: DHCP Remote Code Execution

As of , CVE-2017-12240 in Cisco IOS and IOS XE Software is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch soon.

Exploited
Yes: CISA listed it on 3 March 2022
US federal deadline
24 March 202221 days after CISA listed it. US federal civilian agencies must fix it by then.
Used in ransomware campaigns
Not known to CISA
EPSS score
0.14Higher than 96% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
EPSS when listed
0.04 on 3 March 2022EPSS on the day CISA listed it.
Public exploit
None foundNeither Metasploit nor Exploit-DB lists one.
Fix
No vendor link in CISA's entry

What CISA says to do

Apply updates per vendor instructions.

CISA's required action

What the flaw is

The Dynamic Host Configuration Protocol (DHCP) relay subsystem of Cisco IOS and Cisco IOS XE Software contains a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary code and gain full control of an affected system.

CISA's description

The DHCP relay subsystem of Cisco IOS 12.2 through 15.6 and Cisco IOS XE Software contains a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary code and gain full control of an affected system. The attacker could also cause an affected system to reload, resulting in a denial of service (DoS) condition. The vulnerability is due to a buffer overflow condition in the DHCP relay subsystem of the affected software. An attacker could exploit this vulnerability by sending a crafted DHCP Version 4 (DHCPv4) packet to an affected system. A successful exploit could allow the attacker to execute arbitrary code and gain full control of the affected system or cause the affected system to reload, resulting in a DoS condition. Cisco Bug IDs: CSCsm45390, CSCuw77959.

The CVE record's description, from cisco

CVE published
28 September 2017
Assigned by
cisco
CVSS
9.8 Critical (CVSS 3.1, from CISA-ADP)
CWE-20
Improper Input Validation
CISA SSVC, exploitation
active
CISA SSVC, automatable
yes
CISA SSVC, technical impact
total

Timeline

  1. The CVE record was published.
  2. CISA added it to its list of exploited vulnerabilities.
  3. The US federal deadline to fix it.

IOS and IOS XE Software: other exploited entries

VulnerabilityProductOur groupListedDeadlineEPSS
CVE-2017-6736SNMP Remote Code ExecutionCisco IOS and IOS XE SoftwarePatch this weekEPSS 0.700.70
CVE-2017-6737SNMP Remote Code ExecutionCisco IOS and IOS XE SoftwarePatch soon0.45
CVE-2017-6742SNMP Remote Code ExecutionCisco IOS and IOS XE SoftwarePatch soon0.21
CVE-2018-0151IOS Software and Cisco IOS XE Software Quality of Service Remote Code ExecutionCisco IOS and IOS XE SoftwarePatch soon0.14
CVE-2017-6738SNMP Remote Code ExecutionCisco IOS and IOS XE SoftwarePatch soon0.11
CVE-2017-6739SNMP Remote Code ExecutionCisco IOS and IOS XE SoftwarePatch soon0.11
CVE-2017-6740SNMP Remote Code ExecutionCisco IOS and IOS XE SoftwarePatch soon0.11
CVE-2017-6743SNMP Remote Code ExecutionCisco IOS and IOS XE SoftwarePatch soon0.11
CVE-2017-12237Internet Key Exchange Denial-of-ServiceCisco IOS and IOS XE SoftwarePatch soon0.07
CVE-2018-0172Improper Input ValidationCisco IOS and IOS XE SoftwarePatch soon0.08

All 14 entries for IOS and IOS XE Software

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