# CVE-2024-20263: Security feature bypass in Cisco Small Business Smart and Managed Switches > Unauthenticated attackers can bypass configured Access Control Lists on stacked Cisco Business switches during specific reload or power cycle events. - **Severity:** Medium 5.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** No - **Published:** 26 Jan 2024 - **Updated:** 13 Nov 2024 - **Also known as:** GHSA-h49c-jgw7-9grp ## What is CVE-2024-20263? CVE-2024-20263 is a medium-severity vulnerability in Cisco Small Business Smart and Managed Switches, published on 26 Jan 2024. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description A vulnerability with the access control list (ACL) management within a stacked switch configuration of Cisco Business 250 Series Smart Switches and Business 350 Series Managed Switches could allow an unauthenticated, remote attacker to bypass protection offered by a configured ACL on an affected device. This vulnerability is due to incorrect processing of ACLs on a stacked configuration when either the primary or backup switches experience a full stack reload or power cycle. An attacker could exploit this vulnerability by sending crafted traffic through an affected device. A successful exploit could allow the attacker to bypass configured ACLs, causing traffic to be dropped or forwarded in an unexpected manner. The attacker does not have control over the conditions that result in the device being in the vulnerable state. Note: In the vulnerable state, the ACL would be correctly applied on the primary devices but could be incorrectly applied to the backup devices. Weakness: CWE-284 (Improper Access Control) ## Which versions are affected by CVE-2024-20263? It affects 85 products. Products: Cisco Cbs250-16p-2g Firmware, Cisco Cbs250-16t-2g Firmware, Cisco Cbs250-24fp-4g Firmware, Cisco Cbs250-24fp-4x Firmware, Cisco Cbs250-24p-4g Firmware, Cisco Cbs250-24p-4x Firmware, Cisco Cbs250-24pp-4g Firmware, Cisco Cbs250-24t-4g Firmware, Cisco Cbs250-24t-4x Firmware, Cisco Cbs250-48p-4g Firmware, Cisco Cbs250-48p-4x Firmware, Cisco Cbs250-48pp-4g Firmware, Cisco Cbs250-48t-4g Firmware, Cisco Cbs250-48t-4x Firmware, Cisco Cbs250-8fp-E-2g Firmware, Cisco Cbs250-8p-E-2g Firmware, Cisco Cbs250-8pp-D Firmware, Cisco Cbs250-8pp-E-2g Firmware, Cisco Cbs250-8t-D Firmware, Cisco Cbs250-8t-E-2g Firmware and 65 more. ## How do I fix CVE-2024-20263? No fix has been published for CVE-2024-20263 yet. Limit exposure of the affected software until one is available. ## Is CVE-2024-20263 being exploited? There is no known exploitation of CVE-2024-20263 in the wild and no public exploit code. ## Other vulnerabilities in Cisco Small Business Smart and Managed Switches - [CVE-2021-34739](https://insights.sbomify.com/CVE-2021-34739/): Cisco Small Business Series Switches Session Credentials Replay Vulnerability (high 8.1) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2024-20263 and fix it if it is affected. What it is: CVE-2024-20263 is a medium-severity vulnerability in Cisco Small Business Smart and Managed Switches, published on 26 Jan 2024. 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-2024-20263 in the wild and no public exploit code. Affected product: Cisco Small Business Smart and Managed Switches. 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-2024-20263/ (Markdown: https://insights.sbomify.com/CVE-2024-20263/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2024-20263 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-20263 - OSV: https://osv.dev/vulnerability/CVE-2024-20263 --- From sbomify Insights: https://insights.sbomify.com/CVE-2024-20263/ Summaries are generated and may contain mistakes; the official description above is the record.