# CVE-2022-20933: Cisco Meraki MX and Z3 Teleworker Gateway VPN Denial of Service Vulnerability > Unauthenticated remote attackers can crash the Cisco AnyConnect VPN server via malicious requests, causing service disruption and forcing user re-authentication. - **Severity:** High 8.6 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** No - **Published:** 26 Oct 2022 - **Updated:** 1 Nov 2024 - **Also known as:** GHSA-9vrx-xfr3-hfjj ## What is CVE-2022-20933? CVE-2022-20933 is a high-severity denial of service vulnerability in Cisco Meraki MX Firmware, published on 26 Oct 2022. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description A vulnerability in the Cisco AnyConnect VPN server of Cisco Meraki MX and Cisco Meraki Z3 Teleworker Gateway devices could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient validation of client-supplied parameters while establishing an SSL VPN session. An attacker could exploit this vulnerability by crafting a malicious request and sending it to the affected device. A successful exploit could allow the attacker to cause the Cisco AnyConnect VPN server to crash and restart, resulting in the failure of the established SSL VPN connections and forcing remote users to initiate a new VPN connection and re-authenticate. A sustained attack could prevent new SSL VPN connections from being established. Note: When the attack traffic stops, the Cisco AnyConnect VPN server recovers gracefully without requiring manual intervention. Cisco Meraki has released software updates that address this vulnerability. Weakness: CWE-234 (Failure to Handle Missing Parameter) ## Which versions are affected by CVE-2022-20933? It affects 23 products. Products: Cisco Meraki Mx100 Firmware, Cisco Meraki Mx105 Firmware, Cisco Meraki Mx250 Firmware, Cisco Meraki Mx400 Firmware, Cisco Meraki Mx450 Firmware, Cisco Meraki Mx600 Firmware, Cisco Meraki Mx64 Firmware, Cisco Meraki Mx64w Firmware, Cisco Meraki Mx65 Firmware, Cisco Meraki Mx65w Firmware, Cisco Meraki Mx67 Firmware, Cisco Meraki Mx67cw Firmware, Cisco Meraki Mx67w Firmware, Cisco Meraki Mx68 Firmware, Cisco Meraki Mx68cw Firmware, Cisco Meraki Mx68w Firmware, Cisco Meraki Mx75 Firmware, Cisco Meraki Mx84 Firmware, Cisco Meraki Mx85 Firmware, Cisco Meraki Mx95 Firmware and 3 more. ## How do I fix CVE-2022-20933? No fix has been published for CVE-2022-20933 yet. Limit exposure of the affected software until one is available. ## Is CVE-2022-20933 being exploited? There is no known exploitation of CVE-2022-20933 in the wild and no public exploit code. ## Other vulnerabilities in Cisco Meraki MX Firmware - [CVE-2024-20498](https://insights.sbomify.com/CVE-2024-20498/): Denial of service in Cisco Meraki MX Firmware (high 8.6) - [CVE-2024-20499](https://insights.sbomify.com/CVE-2024-20499/): Denial of service in Cisco Meraki MX Firmware (high 8.6) - [CVE-2024-20501](https://insights.sbomify.com/CVE-2024-20501/): Denial of service in Cisco Meraki MX Firmware (high 8.6) - [CVE-2024-20500](https://insights.sbomify.com/CVE-2024-20500/): Denial of service in Cisco Meraki MX Firmware (medium 5.8) - [CVE-2024-20502](https://insights.sbomify.com/CVE-2024-20502/): Denial of service in Cisco Meraki MX Firmware (medium 5.8) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2022-20933 and fix it if it is affected. What it is: CVE-2022-20933 is a high-severity denial of service vulnerability in Cisco Meraki MX Firmware, published on 26 Oct 2022. An attacker can exploit it over the internet without logging in, with no action from the victim. Exploitation: There is no known exploitation of CVE-2022-20933 in the wild and no public exploit code. Affected product: Cisco Meraki MX Firmware. 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-2022-20933/ (Markdown: https://insights.sbomify.com/CVE-2022-20933/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2022-20933 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-20933 - OSV: https://osv.dev/vulnerability/CVE-2022-20933 --- From sbomify Insights: https://insights.sbomify.com/CVE-2022-20933/ Summaries are generated and may contain mistakes; the official description above is the record.