# CVE-2017-6743: Cisco IOS and IOS XE Software SNMP Remote Code Execution > Authenticated remote attackers can execute arbitrary code or cause reloads on Cisco IOS devices via crafted SNMP packets due to buffer overflows. - **Severity:** High 8.8 (`CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`) - **Exploited in the wild:** Yes, since 3 Mar 2022 (CISA KEV) - **Login needed:** Any signed-in user - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** No - **Published:** 17 Jul 2017 - **Updated:** 21 Oct 2025 - **Also known as:** GHSA-6g39-9vj5-c7xv ## What is CVE-2017-6743? CVE-2017-6743 is a high-severity memory corruption vulnerability in Cisco Ios, published on 17 Jul 2017. Any signed-in user can exploit it over the network, with no action from the victim. ### Official 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. Weakness: CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) ## Which versions are affected by CVE-2017-6743? It affects 2 products. Products: Cisco Ios, Cisco Ios Xe. ## How do I fix CVE-2017-6743? No fix has been published for CVE-2017-6743 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 24 Mar 2022. ## Is CVE-2017-6743 being exploited? Yes. Attackers have exploited CVE-2017-6743 in the wild since at least 3 Mar 2022. ## Other vulnerabilities in Cisco Ios - [CVE-2017-12240](https://insights.sbomify.com/CVE-2017-12240/): Cisco IOS and IOS XE Software DHCP Remote Code Execution (critical 9.8, exploited in the wild) - [CVE-2017-3881](https://insights.sbomify.com/CVE-2017-3881/): Cisco IOS and IOS XE Remote Code Execution (critical 9.8, exploited in the wild) - [CVE-2018-0167](https://insights.sbomify.com/CVE-2018-0167/): Cisco IOS, XR, and XE Software Buffer Overflow (high 8.8, exploited in the wild) - [CVE-2017-6736](https://insights.sbomify.com/CVE-2017-6736/): Cisco IOS and IOS XE Software SNMP Remote Code Execution (high 8.8, exploited in the wild) - [CVE-2017-6737](https://insights.sbomify.com/CVE-2017-6737/): Cisco IOS and IOS XE Software SNMP Remote Code Execution (high 8.8, exploited in the wild) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2017-6743 and fix it if it is affected. What it is: CVE-2017-6743 is a high-severity memory corruption vulnerability in Cisco Ios, published on 17 Jul 2017. Any signed-in user can exploit it over the network, with no action from the victim. Exploitation: Yes. Attackers have exploited CVE-2017-6743 in the wild since at least 3 Mar 2022. Affected product: Cisco Ios. No package-level version data is available, so check the vendor advisory linked from the reference page. Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2017-6743/ (Markdown: https://insights.sbomify.com/CVE-2017-6743/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2017-6743 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-6743 - OSV: https://osv.dev/vulnerability/CVE-2017-6743 --- From sbomify Insights: https://insights.sbomify.com/CVE-2017-6743/ Summaries are generated and may contain mistakes; the official description above is the record.