{"answers":{"affected":"3 open source packages ship an affected version, including github.com/containerd/containerd. It affects 2 products.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-43816 exists.","fix":"Upgrade github.com/containerd/containerd to 1.5.9 or later.","what":"CVE-2021-43816 is a high-severity vulnerability in Fedoraproject Fedora, published on 5 Jan 2022. An attacker needs administrator access to exploit it, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2021-43816 and fix it if it is affected.\n\nWhat it is: CVE-2021-43816 is a high-severity vulnerability in Fedoraproject Fedora, published on 5 Jan 2022. An attacker needs administrator access to exploit it, with no action from the victim.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-43816 exists.\n\nAffected packages and fixed versions:\n- github.com/containerd/containerd (Go): affected from 1.5.0; fixed in 1.5.9\n- github.com/containerd/containerd (Go): affected from 1.5.0; fixed in 1.5.9\n- github.com/containerd/containerd (Go): affected from 1.5.0; fixed in 1.5.9\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-2021-43816/ (Markdown: https://insights.sbomify.com/CVE-2021-43816/index.md)","id":"CVE-2021-43816","markdown":"https://insights.sbomify.com/CVE-2021-43816/index.md","name":"CVE-2021-43816","record":{"aliases":["CLEANSTART-2025-GQ42610","DEBIAN-CVE-2021-43816","GHSA-mvff-h3cj-wj9c","GO-2022-0278","MGASA-2022-0071","UBUNTU-CVE-2021-43816"],"analysis":{"component_type":"container_or_infrastructure","fix_type":"upgrade","impacts":["privilege_escalation","data_read","data_modify"],"network_reachable":"yes","non_default_config":true,"product_category":"container runtime","requires_auth":"high_privilege","summary":"An unprivileged container can read and write privileged host files via hostPath mounts on SELinux systems, requiring an upgrade to containerd.","user_interaction":"not_required","vuln_class":"privilege_escalation"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"fedora","vendor":"fedoraproject"},{"product":"containerd","vendor":"linuxfoundation"}],"cvss":{"score":8,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-281","name":"Improper Preservation of Permissions"}],"description":"containerd is an open source container runtime. On installations using SELinux, such as EL8 (CentOS, RHEL), Fedora, or SUSE MicroOS, with containerd since v1.5.0-beta.0 as the backing container runtime interface (CRI), an unprivileged pod scheduled to the node may bind mount, via hostPath volume, any privileged, regular file on disk for complete read/write access (sans delete). Such is achieved by placing the in-container location of the hostPath volume mount at either `/etc/hosts`, `/etc/hostname`, or `/etc/resolv.conf`. These locations are being relabeled indiscriminately to match the container process-label which effectively elevates permissions for savvy containers that would not normally be able to access privileged host files. This issue has been resolved in version 1.5.9. Users are advised to upgrade as soon as possible.","ecosystems":["Go"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"Improper Preservation of Permissions in containerd","id":"CVE-2021-43816","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Go","product":"fedoraproject:fedora","products":["fedoraproject:fedora"],"type":"privilege_escalation","year":"2021"},"n_packages":3,"n_references":6,"next":{"headline":"Reflected Cross-Site-Scripting vulnerability in Collabora Online","id":"CVE-2021-43817"},"packages":[{"ecosystem":"Go","fixed":["1.5.9"],"introduced":["1.5.0"],"last_affected":[],"package":"github.com/containerd/containerd","purl":null,"source":"GHSA-mvff-h3cj-wj9c"},{"ecosystem":"Go","fixed":["1.5.9"],"introduced":["1.5.0"],"last_affected":[],"package":"github.com/containerd/containerd","purl":"pkg:golang/github.com/containerd/containerd","source":"GHSA-mvff-h3cj-wj9c"},{"ecosystem":"Go","fixed":["1.5.9"],"introduced":["1.5.0"],"last_affected":[],"package":"github.com/containerd/containerd","purl":"pkg:golang/github.com/containerd/containerd","source":"GO-2022-0278"}],"prev":{"headline":"Grafana directory traversal for `.cvs` files","id":"CVE-2021-43815"},"products":["containerd"],"published":"2022-01-05","related":[{"cvss_score":9.8,"headline":"PHP-CGI OS Command Injection","id":"CVE-2024-4577","kev_date_added":"2024-06-12","published":"2024-06-09"},{"cvss_score":9.8,"headline":"Grafana Authentication Bypass","id":"CVE-2021-39226","kev_date_added":"2022-08-25","published":"2021-10-05"},{"cvss_score":9.8,"headline":"VMware ESXi and Horizon DaaS OpenSLP Heap-Based Buffer Overflow","id":"CVE-2019-5544","kev_date_added":"2021-11-03","published":"2019-12-06"},{"cvss_score":9.6,"headline":"Google Chromium V8 Type Confusion","id":"CVE-2024-4947","kev_date_added":"2024-05-20","published":"2024-05-15"},{"cvss_score":9.6,"headline":"Google Chromium Visuals Use-After-Free","id":"CVE-2024-4671","kev_date_added":"2024-05-13","published":"2024-05-09"},{"cvss_score":9.6,"headline":"Google Chromium Mojo Insufficient Data Validation","id":"CVE-2022-3075","kev_date_added":"2022-09-08","published":"2022-09-26"},{"cvss_score":9.6,"headline":"Google Chromium Indexed DB API Use-After-Free","id":"CVE-2021-30633","kev_date_added":"2021-11-03","published":"2021-10-08"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CC BY 4.0","name":"Go Vulnerability Database","prefix":"GO"},{"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":"no","exploitation":"poc","technical_impact":"total"},"state":"PUBLISHED","updated":"2025-04-22","vendors":["containerd"]},"summary":"An unprivileged container can read and write privileged host files via hostPath mounts on SELinux systems, requiring an upgrade to containerd.","url":"https://insights.sbomify.com/CVE-2021-43816/"}