CVE-2017-12240
Actively exploited. CVE-2017-12240 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-03-03) — exploitation has been observed in the wild, and US federal agencies are required to remediate it under BOD 22-01. Treat patching as urgent.
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.
CSIRTS triage
- What
- A vulnerability in the DHCP relay subsystem allows remote attackers to execute arbitrary code.
- Who is affected
- Unauthenticated remote attackers can exploit this vulnerability in Cisco IOS and IOS XE Software.
- Urgency
- Remediation is critical due to the high severity and active exploitation.
- Action
- Update Cisco IOS and IOS XE Software to the latest version.
AI-assisted analysis generated from the source advisory — verify against the original.
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Exploitation outlook
- Exploitation confirmedAlready exploited in the wild (CISA KEV) — the prediction phase is over. Patch now. Riskier than 96% of all EPSS-scored CVEs.
Advisory coverage (1)
- criticalexploitedCVE-2017-12240: Cisco IOS and IOS XE Software DHCP Remote Code Execution Vulnerabilitycisa-kev · 2022-03-03
External references
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