{"answers":{"affected":"It affects 2 products.","exploited":"There is no known exploitation of CVE-2021-21994 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2021-21994 yet. Limit exposure of the affected software until one is available.","what":"CVE-2021-21994 is a critical authentication bypass vulnerability in Vmware Cloud Foundation, published on 13 Jul 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-2021-21994 and fix it if it is affected.\n\nWhat it is: CVE-2021-21994 is a critical authentication bypass vulnerability in Vmware Cloud Foundation, published on 13 Jul 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-2021-21994 in the wild and no public exploit code.\n\nAffected product: Vmware Cloud Foundation. 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-2021-21994/ (Markdown: https://insights.sbomify.com/CVE-2021-21994/index.md)","id":"CVE-2021-21994","markdown":"https://insights.sbomify.com/CVE-2021-21994/index.md","name":"CVE-2021-21994","record":{"aliases":["GHSA-4643-h6pq-84f9"],"analysis":{"component_type":"server_software","fix_type":"patch","impacts":["security_bypass"],"network_reachable":"yes","non_default_config":false,"product_category":"VMware ESXi","requires_auth":"none","summary":"Attackers can bypass SFCB authentication in VMware ESXi by sending crafted requests to port 5989, requiring immediate patching.","user_interaction":"not_required","vuln_class":"auth_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"vmware","cpe":[{"product":"cloud_foundation","vendor":"vmware"},{"product":"esxi","vendor":"vmware"}],"cvss":{"score":9.8,"severity":"critical","source":"nvd","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-287","name":"Improper Authentication"}],"description":"SFCB (Small Footprint CIM Broker) as used in ESXi has an authentication bypass vulnerability. A malicious actor with network access to port 5989 on ESXi may exploit this issue to bypass SFCB authentication by sending a specially crafted request.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":"2026-08-15","github_poc":1,"max_poc_stars":0,"metasploit":0,"nuclei":0,"refs":[{"date":"2026-08-15T08:21:38Z","kind":"github_poc","ref":"https://github.com/mreza-en/cve-2021-21994_POC","stars":0,"title":null}],"tier":"poc_unverified"},"has_fix":null,"headline":"Auth bypass in VMware ESXi and VMware Cloud Foundation","id":"CVE-2021-21994","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"vmware:cloud_foundation","products":["vmware:cloud_foundation","vmware:esxi"],"type":"auth_bypass","year":"2021"},"n_packages":0,"n_references":1,"next":{"headline":"Denial of service in VMware ESXi and VMware Cloud Foundation","id":"CVE-2021-21995"},"packages":[],"prev":{"headline":"Server-side request forgery in VMware vCenter Server, VMware Cloud Foundation","id":"CVE-2021-21993"},"products":["VMware ESXi and VMware Cloud Foundation"],"published":"2021-07-13","related":[{"cvss_score":9.8,"headline":"VMware vCenter Server Heap-Based Buffer Overflow","id":"CVE-2024-38812","kev_date_added":"2024-11-20","published":"2024-09-17"},{"cvss_score":9.8,"headline":"Broadcom VMware vCenter Server Out-of-bounds Write","id":"CVE-2024-37079","kev_date_added":"2026-01-23","published":"2024-06-18"},{"cvss_score":9.8,"headline":"VMware Workspace ONE Access and Identity Manager Server-Side Template Injection","id":"CVE-2022-22954","kev_date_added":"2022-04-14","published":"2022-04-11"},{"cvss_score":9.8,"headline":"VMware vCenter Server File Upload","id":"CVE-2021-22005","kev_date_added":"2021-11-03","published":"2021-09-23"},{"cvss_score":9.8,"headline":"VMware vCenter Server Improper Input Validation","id":"CVE-2021-21985","kev_date_added":"2021-11-03","published":"2021-05-26"},{"cvss_score":9.8,"headline":"VMware Server Side Request Forgery in vRealize Operations Manager API","id":"CVE-2021-21975","kev_date_added":"2022-01-18","published":"2021-03-31"},{"cvss_score":9.8,"headline":"VMware vCenter Server Remote Code Execution","id":"CVE-2021-21972","kev_date_added":"2021-11-03","published":"2021-02-24"}],"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)"},{"class":"open","licence":"CC0","name":"PoC-in-GitHub"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2024-08-03","vendors":["n/a"]},"summary":"Attackers can bypass SFCB authentication in VMware ESXi by sending crafted requests to port 5989, requiring immediate patching.","url":"https://insights.sbomify.com/CVE-2021-21994/"}