CVE-2017-6736

HIGH KEV

Cisco IOS and IOS XE - Authenticated Remote Code Execution via SNMP Buffer Overflow

Title source: llm
STIX 2.1

Exploitation Summary

CVE-2017-6736 is actively exploited and listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added March 3, 2022. EIP tracks 4 public exploits from researchers including Artem Kondratenko, plyrthn, msztankowski.

AI-analyzed exploit summary This exploit leverages a buffer overflow in Cisco IOS SNMP service (CVE-2017-6736) to achieve remote code execution by writing shellcode to a specific memory address and redirecting execution flow. It targets Cisco 2800 series routers with specific firmware versions.

Description

The Simple Network Management Protocol (SNMP) subsystem of Cisco IOS and IOS XE Software contains multiple vulnerabilities that could allow an authenticated, remote attacker to remotely execute code on an affected system or cause an affected system to reload. An attacker could exploit these vulnerabilities by sending a crafted SNMP packet to an affected system via IPv4 or IPv6. Only traffic directed to an affected system can be used to exploit these vulnerabilities. The vulnerabilities are due to a buffer overflow condition in the SNMP subsystem of the affected software. The vulnerabilities affect all versions of SNMP - Versions 1, 2c, and 3. To exploit these vulnerabilities via SNMP Version 2c or earlier, the attacker must know the SNMP read-only community string for the affected system. To exploit these vulnerabilities via SNMP Version 3, the attacker must have user credentials for the affected system. A successful exploit could allow the attacker to execute arbitrary code and obtain full control of the affected system or cause the affected system to reload. Customers are advised to apply the workaround as contained in the Workarounds section below. Fixed software information is available via the Cisco IOS Software Checker. All devices that have enabled SNMP and have not explicitly excluded the affected MIBs or OIDs should be considered vulnerable. There are workarounds that address these vulnerabilities.

Exploits (4)

exploitdb WORKING POC
by Artem Kondratenko · pythonremotehardware
https://www.exploit-db.com/exploits/43450

This exploit leverages a buffer overflow in Cisco IOS SNMP service (CVE-2017-6736) to achieve remote code execution by writing shellcode to a specific memory address and redirecting execution flow. It targets Cisco 2800 series routers with specific firmware versions.

Classification
Working Poc 100%
Attack Type
Rce
Complexity
Moderate
Reliability
Reliable
Target: Cisco IOS Software, 2800 Software (C2800NM-ADVENTERPRISEK9-M), Version 15.1(4)M12a
Auth required
Prerequisites: Read-only SNMP community string · Target device with vulnerable firmware
devstral-2 · analyzed Feb 16, 2026 Full analysis →
nomisec WORKING POC
by plyrthn · poc
https://github.com/plyrthn/CiscoSpectreTakeover

This repository provides a proof-of-concept exploit chain combining CVE-2017-6736 (Cisco SNMP RCE) with Spectre vulnerabilities (CVE-2017-5753 and CVE-2017-5715). It leverages the Cisco exploit to redirect traffic through a Spectre login page.

Classification
Working Poc 90%
Attack Type
Rce
Complexity
Moderate
Reliability
Reliable
Target: Cisco 1841+2600 Router
No auth needed
Prerequisites: Access to vulnerable Cisco router · Network connectivity to the target
devstral-2 · analyzed Feb 16, 2026 Full analysis →
nomisec WORKING POC
by plyrthn · poc
https://github.com/plyrthn/CiscoIOSSNMPToolkit

This repository contains a PoC exploit for CVE-2017-6736, a buffer overflow vulnerability in Cisco IOS SNMP. The exploit uses a combination of SNMP overflow and telnet commands to achieve remote code execution and modify the router's configuration.

Classification
Working Poc 90%
Attack Type
Rce
Complexity
Moderate
Reliability
Reliable
Target: Cisco IOS (specific versions vulnerable to CVE-2017-6736)
Auth required
Prerequisites: SNMP access to the target device · Telnet access with known credentials
devstral-2 · analyzed Feb 16, 2026 Full analysis →
nomisec WORKING POC
by msztankowski · poc
https://github.com/msztankowski/CiscoIOSSNMPToolkit

This repository contains a PoC exploit for CVE-2017-6736, a buffer overflow vulnerability in Cisco IOS SNMP. The exploit uses a crafted SNMP packet to achieve remote code execution and then configures the router via Telnet to modify its routing table.

Classification
Working Poc 90%
Attack Type
Rce
Complexity
Moderate
Reliability
Reliable
Target: Cisco IOS (specific versions affected by CVE-2017-6736)
Auth required
Prerequisites: SNMP access to the target device · Telnet credentials (default 'cisco/cisco' in the PoC)
devstral-2 · analyzed Feb 16, 2026 Full analysis →

Scores

CVSS v3 8.8
EPSS 0.7056
EPSS Percentile 99.3%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation active
Automatable no
Technical Impact total

Details

CISA KEV 2022-03-03
VulnCheck KEV 2019-04-17
InTheWild.io 2019-04-17
ENISA EUVD EUVD-2017-15790
CWE
CWE-119
Status published
Products (50)
cisco/ios 12.0 - 12.4
Cisco/IOS 12.0(1)
Cisco/IOS 12.0(1)T
Cisco/IOS 12.0(1)T1
Cisco/IOS 12.0(1)XE
Cisco/IOS 12.0(10)
Cisco/IOS 12.0(10)S
Cisco/IOS 12.0(10)S1
Cisco/IOS 12.0(10)S2
Cisco/IOS 12.0(10)S3
... and 40 more
Published Jul 17, 2017
KEV Added Mar 03, 2022
Tracked Since Feb 18, 2026