{"id":"CVE-2021-38199","title":"fs/nfs/nfs4client.c in the Linux kernel before 5.13.4 has incorrect connection-setup ordering, which allows operators of remote NFSv4 servers to cause a denial of service (hanging of mounts) by arranging for those servers to be unreachab…","summary":"fs/nfs/nfs4client.c in the Linux kernel before 5.13.4 has incorrect connection-setup ordering, which allows operators of remote NFSv4 servers to cause a denial of service (hanging of mounts) by arranging for those servers to be unreachab…","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","vendor":"netapp","product":"hci_management_node","affected":["linux_kernel < 5.13.4","hci_bootstrap_os","hci_management_node","solidfire","element_software","debian_linux = 9.0","debian_linux = 11.0"],"patched":["linux_kernel 5.13.4"],"published":"2021-08-08","updated":"2026-10-08","sourceUpdated":"2026-10-08T21:17:39.333","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2021-38199","references":[{"url":"https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.13.4","label":"cve@mitre.org"},{"url":"https://github.com/torvalds/linux/commit/dd99e9f98fbf423ff6d365b37a98e8879170f17c","label":"cve@mitre.org"},{"url":"https://lists.debian.org/debian-lts-announce/2021/10/msg00010.html","label":"cve@mitre.org"},{"url":"https://lists.debian.org/debian-lts-announce/2021/12/msg00012.html","label":"cve@mitre.org"},{"url":"https://security.netapp.com/advisory/ntap-20210902-0010/","label":"cve@mitre.org"},{"url":"https://www.debian.org/security/2021/dsa-4978","label":"cve@mitre.org"},{"url":"https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.13.4","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/torvalds/linux/commit/dd99e9f98fbf423ff6d365b37a98e8879170f17c","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2021/10/msg00010.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2021/12/msg00012.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20210902-0010/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.debian.org/security/2021/dsa-4978","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-38199.json"},{"url":"https://access.redhat.com/security/cve/CVE-2021-38199"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1992271"},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-38199"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-38199"},{"url":"https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=dd99e9f98fbf423ff6d365b37a98e8879170f17c"}],"tags":["nvd","csaf","vex","red-hat","cve.org"],"epss":0.01245,"epssPercentile":0.69144,"ingestedAt":"2026-10-08T22:11:53.740Z","cwe":["CWE-665"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-10-08T21:00:25.929879Z"},"slug":"CVE-2021-38199","body":"## Overview\n\nfs/nfs/nfs4client.c in the Linux kernel before 5.13.4 has incorrect connection-setup ordering, which allows operators of remote NFSv4 servers to cause a denial of service (hanging of mounts) by arranging for those servers to be unreachable during trunking detection.\n\n## Affected\n\n- `linux_kernel < 5.13.4`\n- `hci_bootstrap_os`\n- `hci_management_node`\n- `solidfire`\n- `element_software`\n- `debian_linux = 9.0`\n- `debian_linux = 11.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 5.13.4`\n\n## Vendor advisories\n\n- **Red Hat VEX** · Low · affected: Red Hat Enterprise Linux 8 · no fix planned: Red Hat Enterprise Linux 8 · updated 2026-10-08 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-38199.json)","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0.2,"exploitation":0,"ransomware":0},"changes":[]}