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CriticalCISA KEVExploited in the wildPublic exploit

Cisco 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, allowing a crafted Smart Install message sent to TCP port 4786 to trigger a buffer overflow on an affected device. Cisco states that successful exploitation by an unauthenticated remote attacker can cause a device reload, force the device into an indefinite loop that results in a watchdog crash, or enable arbitrary code execution on the device. The issue affects devices with Smart Install exposed and has been widely referenced as a Cisco Smart Install RCE vulnerability.

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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 result in denial of service through device reloads or watchdog crashes, interrupting routing and switching functions and potentially disrupting dependent networks or industrial environments. In the more severe case, the attacker can execute arbitrary code on the affected Cisco IOS or IOS XE device, enabling full compromise of the network device and subsequent malicious configuration changes, credential exposure, persistence, traffic interception, and use of the device as a foothold for further intrusion activity.

Mitigation

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

If patching is not possible, disable Smart Install using the 'no vstack' command where operationally feasible. Restrict or block access to TCP port 4786 with ACLs or perimeter filtering, especially from untrusted networks. Limit exposure of management services, follow Cisco hardening guidance, disable insecure services such as Telnet where possible, prefer SSH, strengthen authentication and SNMP configuration, and monitor for anomalous Smart Install traffic or oversized SMI payloads associated with exploitation attempts.

Remediation

Patch, then assume compromise.

Apply Cisco-provided software updates that fix CVE-2018-0171 on supported Cisco IOS and IOS XE devices. For affected downstream products based on Cisco IOS/IOS XE, vendor guidance in the provided content includes upgrading Allen-Bradley Stratix and ArmorStratix devices to firmware 15.2(6)E1 or later where applicable. Replace or retire end-of-life devices that cannot receive patches. Verify that Smart Install is not exposed unnecessarily and review device configurations for unauthorized changes if compromise is suspected.
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.

This page is what’s public. Mallory adds the parts that aren’t: which of your assets are affected, which adversaries are exploiting it right now, which detections to deploy, and what to do tonight.
Exposure mapping

Query your assets running an affected version, and investigate the blast radius.

Threat actor evidence17

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.