CVE-2018-0171
Cisco IOS and IOS XE Software improperly validates packet data, allowing an unauthenticated, remote attacker to trigger a reload of an affected device, cause a denial-of-service (DoS) condition, or perform code execution on the affected device.
A vulnerability in the Smart Install feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to trigger a reload of an affected device, resulting in a denial of service (DoS) condition, or to execute arbitrary code on an affected device. The vulnerability is due to improper validation of packet data. An attacker could exploit this vulnerability by sending a crafted Smart Install message to an affected device on TCP port 4786. A successful exploit could allow the attacker to cause a buffer overflow on the affected device, which could have the following impacts: Triggering a reload of the device, Allowing the attacker to execute arbitrary code on the device, Causing an indefinite loop on the affected device that triggers a watchdog crash. Cisco Bug IDs: CSCvg76186.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- securityfocus.com/bid/103538Third Party AdvisoryVDB Entry
- securitytracker.com/id/1040580Third Party AdvisoryVDB Entry
- ics-cert.us-cert.gov/advisories/ICSA-18-107-04Third Party AdvisoryUS Government Resource
- ics-cert.us-cert.gov/advisories/ICSA-18-107-05Third Party AdvisoryUS Government Resource
- tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-smi2Vendor Advisory
- darkreading.com/perimeter/attackers-exploit-cisco-switch-issue-as-vendor-warns-of-yet-another-critical-flaw/d/d-id/1331490Press/Media Coverage
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-0171US Government Resource
Actively exploited. Patch immediately.
- Exploitation
- Confirmed in the wild (CISA KEV)
- Federal remediation deadline
- Overdue by 1638 days
- CVSS
- 9.8 CRITICAL
- EPSS (30-day exploit probability)
- 99.5% · top 1% of all CVEs
- Weakness
- CWE-20
- Attack vector
- Network, remotely reachable
- Preconditions
- No privileges and no user interaction
- 1.Apply updates per vendor instructions.
- 2.Treat as emergency change: patch or isolate internet-facing instances first.
- 3.Review exposure: confirm which instances are reachable from the internet and restrict access until patched.
- 4.Hunt for compromise: review logs for the disclosure window, not just from the patch date.
Assessment is derived automatically from the live signals above; verify against your own asset inventory.