{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-1523 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2021-1523 yet. Limit exposure of the affected software until one is available.","what":"CVE-2021-1523 is a high-severity denial of service vulnerability in Cisco Nx-Os, published on 25 Aug 2021. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2021-1523 and fix it if it is affected.\n\nWhat it is: CVE-2021-1523 is a high-severity denial of service vulnerability in Cisco Nx-Os, published on 25 Aug 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2021-1523 in the wild and no public exploit code.\n\nAffected product: Cisco Nx-Os. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. 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.\n2. 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.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2021-1523/ (Markdown: https://insights.sbomify.com/CVE-2021-1523/index.md)","id":"CVE-2021-1523","markdown":"https://insights.sbomify.com/CVE-2021-1523/index.md","name":"CVE-2021-1523","record":{"aliases":["GHSA-f58x-5qwh-88r6"],"analysis":{"component_type":"network_device","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Cisco Nexus Switch","requires_auth":"none","summary":"Unauthenticated remote attackers can cause a queue wedge on Cisco Nexus switches, dropping control plane traffic and requiring a power cycle to recover.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"cisco","cpe":[{"product":"nx-os","vendor":"cisco"}],"cvss":{"score":8.6,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-772","name":"Missing Release of Resource after Effective Lifetime"}],"description":"A vulnerability in Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) Mode could allow an unauthenticated, remote attacker to cause a queue wedge on a leaf switch, which could result in critical control plane traffic to the device being dropped. This could result in one or more leaf switches being removed from the fabric. This vulnerability is due to mishandling of ingress TCP traffic to a specific port. An attacker could exploit this vulnerability by sending a stream of TCP packets to a specific port on a Switched Virtual Interface (SVI) configured on the device. A successful exploit could allow the attacker to cause a specific packet queue to queue network buffers but never process them, leading to an eventual queue wedge. This could cause control plane traffic to be dropped, resulting in a denial of service (DoS) condition where the leaf switches are unavailable. Note: This vulnerability requires a manual intervention to power-cycle the device to recover.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":null,"headline":"Cisco Nexus 9000 Series Fabric Switches ACI Mode Queue Wedge Denial of Service Vulnerability","id":"CVE-2021-1523","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"cisco:nx-os","products":["cisco:nx-os"],"type":"denial_of_service","year":"2021"},"n_packages":0,"n_references":1,"next":{"headline":"Cisco Meeting Server API Denial of Service Vulnerability","id":"CVE-2021-1524"},"packages":[],"prev":{"headline":"Cisco Connected Mobile Experiences Strong Authentication Requirements Enforcement Bypass","id":"CVE-2021-1522"},"products":["Cisco NX-OS System Software in ACI Mode"],"published":"2021-08-25","related":[{"cvss_score":6,"headline":"Cisco NX-OS Command Injection","id":"CVE-2024-20399","kev_date_added":"2024-07-02","published":"2024-07-01"},{"cvss_score":9.8,"headline":"Cisco NX-OS Software Unauthenticated Arbitrary File Actions Vulnerability","id":"CVE-2021-1361","kev_date_added":null,"published":"2021-02-24"},{"cvss_score":9.8,"headline":"Memory corruption in Cisco NX-OS unknown","id":"CVE-2018-0301","kev_date_added":null,"published":"2018-06-20"},{"cvss_score":9.8,"headline":"Memory corruption in n/a","id":"CVE-2016-1453","kev_date_added":null,"published":"2016-10-06"},{"cvss_score":9.8,"headline":"Hardcoded credentials in n/a","id":"CVE-2016-1341","kev_date_added":null,"published":"2016-02-24"},{"cvss_score":8.8,"headline":"Cisco NX-OS Software NX-API Command Injection Vulnerability","id":"CVE-2022-20650","kev_date_added":null,"published":"2022-02-23"},{"cvss_score":8.8,"headline":"Cisco NX-OS Software Data Management Engine Remote Code Execution Vulnerability","id":"CVE-2020-3415","kev_date_added":null,"published":"2020-08-27"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"yes","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2024-11-07","vendors":["Cisco"]},"summary":"Unauthenticated remote attackers can cause a queue wedge on Cisco Nexus switches, dropping control plane traffic and requiring a power cycle to recover.","url":"https://insights.sbomify.com/CVE-2021-1523/"}