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CriticalCISA KEVExploited in the wildPublic exploit

Cisco IOS and IOS XE Smart Install Remote Code Execution

IdentifiersCVE-2018-0171CWE-20· Improper Input Validation

CVE-2018-0171 is a vulnerability in the Smart Install feature of Cisco IOS Software and Cisco IOS XE Software. The flaw is caused by improper validation of packet data in Smart Install message handling, reachable over TCP port 4786. A remote, unauthenticated attacker can send a crafted Smart Install message to a vulnerable device and trigger a buffer overflow. Successful exploitation can result in arbitrary code execution on the affected device, a forced device reload causing denial of service, or an indefinite loop that leads to a watchdog crash.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation can fully compromise the affected network device by enabling unauthenticated remote arbitrary code execution. Where code execution is not achieved, exploitation can still disrupt operations by forcing a reload or causing the device to enter an indefinite loop and crash, resulting in denial of service. Because the affected products are routers and switches, compromise can also enable follow-on actions such as configuration theft, credential exposure from startup/running configurations, unauthorized account creation, management-plane modification, persistence, traffic interception, and lateral movement.

Mitigation

If you can’t patch tonight, do this now.

If Smart Install is not required, disable it with the Cisco command "no vstack". Restrict or block access to TCP port 4786 using ACLs or perimeter/internal firewall policy, especially from untrusted networks. Minimize exposure of management services, isolate network infrastructure, follow Cisco hardening guidance, prefer SSH over Telnet, and monitor for anomalous Smart Install traffic or oversized SMI payloads indicative of exploitation attempts.

Remediation

Patch, then assume compromise.

Upgrade Cisco IOS or IOS XE to a fixed software release provided by Cisco. For affected downstream products based on Cisco IOS/IOS XE, apply vendor firmware updates where available; the provided content specifically notes Rockwell remediation to firmware FRN 15.2(6)E1 or later for affected Stratix and ArmorStratix switches. Replace or retire unsupported/end-of-life devices that cannot be patched. Validate that Smart Install is no longer exposed after remediation.
PUBLIC EXPLOITS

Exploits

1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos (1 hidden).

VALID 1 / 2 TOTALView more in app
Cisco-Smart-ExploitMaturityPoCVerified exploit

This repository provides a Python 3 exploit script (cisco-se.py) targeting Cisco devices vulnerable to CVE-2018-0171 (SmartInstall Remote Code Execution/Config Extraction). The script connects to the target device on TCP port 4786, sends crafted payloads to exploit the SmartInstall protocol, and then uses TFTP (port 69) to download the device's 'startup-config' file. After downloading, it parses the configuration to extract and decrypt secret 7 password hashes (using the external 'c7decrypt' tool), plaintext passwords, and SNMP community strings. The script supports targeting a single IP, a list of IPs, or analyzing a standalone configuration file. The repository includes a README with usage instructions and a requirements.txt specifying the tftpy library. The exploit is operational, providing real extraction and parsing of sensitive configuration data from vulnerable Cisco devices.

AlrikRrDisclosed Feb 1, 2023pythonnetwork
EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType
Cisco SystemsIosoperating_system

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

What this page doesn’t show

The version that knows your environment.

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Exposure mapping

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Threat actor evidence13

Every observed campaign linking this CVE to a named adversary.

Associated malware3

Malware families riding this exploit, with evidence and IOCs.

Detection signatures1

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity43

Community discussion across Reddit, Mastodon, and other social sources.