{"id":"CVE-2021-38199","details":"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 unreachable during trunking detection.","modified":"2026-04-11T21:23:10.704489Z","published":"2021-08-08T20:15:07.073Z","references":[{"type":"ADVISORY","url":"https://lists.debian.org/debian-lts-announce/2021/10/msg00010.html"},{"type":"ADVISORY","url":"https://lists.debian.org/debian-lts-announce/2021/12/msg00012.html"},{"type":"ADVISORY","url":"https://security.netapp.com/advisory/ntap-20210902-0010/"},{"type":"ADVISORY","url":"https://www.debian.org/security/2021/dsa-4978"},{"type":"FIX","url":"https://github.com/torvalds/linux/commit/dd99e9f98fbf423ff6d365b37a98e8879170f17c"},{"type":"FIX","url":"https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.13.4"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/torvalds/linux","events":[{"introduced":"0"},{"fixed":"dd99e9f98fbf423ff6d365b37a98e8879170f17c"}]},{"type":"GIT","repo":"https://github.com/torvalds/linux","events":[{"introduced":"0"},{"fixed":"dd99e9f98fbf423ff6d365b37a98e8879170f17c"}]}],"versions":["v2.6.12-rc2","v2.6.12-rc3","v2.6.12-rc4","v2.6.13","v2.6.13-rc1","v2.6.13-rc2","v2.6.13-rc3","v2.6.13-rc4","v2.6.13-rc5","v2.6.13-rc6","v2.6.13-rc7","v2.6.14-rc1","v2.6.14-rc2","v2.6.14-rc3","v2.6.15-rc1","v2.6.15-rc2","v2.6.15-rc4","v2.6.15-rc5","v2.6.15-rc7","v2.6.16","v2.6.16-rc1","v2.6.16-rc2","v2.6.16-rc3","v2.6.16-rc4","v2.6.16-rc5","v2.6.16-rc6","v2.6.17","v2.6.17-rc1","v2.6.17-rc2","v2.6.17-rc3","v2.6.17-rc4","v2.6.17-rc5","v2.6.17-rc6","v2.6.18","v2.6.18-rc1","v2.6.18-rc2","v2.6.18-rc3","v2.6.18-rc5","v2.6.18-rc6","v2.6.19-rc1","v2.6.19-rc2","v2.6.20-rc1","v2.6.20-rc2","v2.6.20-rc3","v2.6.20-rc4","v2.6.20-rc5","v2.6.20-rc6","v2.6.20-rc7","v2.6.21","v2.6.21-rc1","v2.6.21-rc2","v2.6.21-rc3","v2.6.21-rc4","v2.6.21-rc5","v2.6.21-rc6","v2.6.21-rc7","v2.6.22","v2.6.22-rc1","v2.6.22-rc2","v2.6.22-rc3","v2.6.22-rc4","v2.6.22-rc5","v2.6.22-rc6","v2.6.22-rc7","v2.6.23","v2.6.23-rc1","v2.6.23-rc2","v2.6.23-rc3","v2.6.23-rc4","v2.6.23-rc5","v2.6.23-rc6","v2.6.23-rc7","v2.6.23-rc8","v2.6.23-rc9","v2.6.24","v2.6.24-rc1","v2.6.24-rc2","v2.6.24-rc3","v2.6.24-rc4","v2.6.24-rc5","v2.6.24-rc6","v2.6.24-rc7","v2.6.24-rc8","v2.6.25","v2.6.25-rc1","v2.6.25-rc2","v2.6.25-rc3","v2.6.25-rc4","v2.6.25-rc5","v2.6.25-rc6","v2.6.25-rc7","v2.6.25-rc8","v2.6.25-rc9","v2.6.26","v2.6.26-rc1","v2.6.26-rc2","v2.6.26-rc3","v2.6.26-rc4","v2.6.26-rc5","v2.6.26-rc6","v2.6.26-rc7","v2.6.26-rc8","v2.6.26-rc9","v2.6.27","v2.6.27-rc1","v2.6.27-rc2","v2.6.27-rc3","v2.6.27-rc4","v2.6.27-rc5","v2.6.27-rc6","v2.6.27-rc7","v2.6.27-rc8","v2.6.27-rc9","v2.6.28","v2.6.28-rc1","v2.6.28-rc2","v2.6.28-rc3","v2.6.28-rc4","v2.6.28-rc5","v2.6.28-rc6","v2.6.28-rc7","v2.6.28-rc8","v2.6.28-rc9","v2.6.29","v2.6.29-rc1","v2.6.29-rc2","v2.6.29-rc3","v2.6.29-rc4","v2.6.29-rc5","v2.6.29-rc6","v2.6.29-rc7","v2.6.29-rc8","v2.6.30","v2.6.30-rc1","v2.6.30-rc2","v2.6.30-rc3","v2.6.30-rc4","v2.6.30-rc5","v2.6.30-rc6","v2.6.30-rc7","v2.6.30-rc8","v2.6.31","v2.6.31-rc1","v2.6.31-rc2","v2.6.31-rc3","v2.6.31-rc4","v2.6.31-rc5","v2.6.31-rc6","v2.6.31-rc7","v2.6.31-rc8","v2.6.31-rc9","v2.6.32","v2.6.32-rc1","v2.6.32-rc2","v2.6.32-rc3","v2.6.32-rc4","v2.6.32-rc5","v2.6.32-rc6","v2.6.32-rc7","v2.6.32-rc8","v2.6.33","v2.6.33-rc1","v2.6.33-rc2","v2.6.33-rc3","v2.6.33-rc4","v2.6.33-rc5","v2.6.33-rc6","v2.6.33-rc7","v2.6.33-rc8","v2.6.34","v2.6.34-rc1","v2.6.34-rc2","v2.6.34-rc3","v2.6.34-rc4","v2.6.34-rc5","v2.6.34-rc6","v2.6.34-rc7","v2.6.35","v2.6.35-rc1","v2.6.35-rc2","v2.6.35-rc3","v2.6.35-rc4","v2.6.35-rc5","v2.6.35-rc6","v2.6.36","v2.6.36-rc1","v2.6.36-rc2","v2.6.36-rc3","v2.6.36-rc4","v2.6.36-rc5","v2.6.36-rc6","v2.6.36-rc7","v2.6.36-rc8","v2.6.37","v2.6.37-rc1","v2.6.37-rc2","v2.6.37-rc3","v2.6.37-rc4","v2.6.37-rc5","v2.6.37-rc6","v2.6.37-rc7","v2.6.37-rc8","v2.6.38","v2.6.38-rc1","v2.6.38-rc2","v2.6.38-rc3","v2.6.38-rc4","v2.6.38-rc5","v2.6.38-rc6","v2.6.38-rc7","v2.6.38-rc8","v2.6.39","v2.6.39-rc1","v2.6.39-rc2","v2.6.39-rc3","v2.6.39-rc4","v2.6.39-rc5","v2.6.39-rc6","v2.6.39-rc7","v3.0","v3.0-rc1","v3.0-rc2","v3.0-rc3","v3.0-rc4","v3.0-rc5","v3.0-rc6","v3.0-rc7","v3.1","v3.1-rc1","v3.1-rc10","v3.1-rc2","v3.1-rc3","v3.1-rc4","v3.1-rc5","v3.1-rc6","v3.1-rc7","v3.1-rc8","v3.1-rc9","v3.10","v3.10-rc1","v3.10-rc2","v3.10-rc3","v3.10-rc4","v3.10-rc5","v3.10-rc6","v3.10-rc7","v3.11","v3.11-rc1","v3.11-rc2","v3.11-rc3","v3.11-rc4","v3.11-rc5","v3.11-rc6","v3.11-rc7","v3.12","v3.12-rc1","v3.12-rc2","v3.12-rc3","v3.12-rc4","v3.12-rc5","v3.12-rc6","v3.12-rc7","v3.13","v3.13-rc1","v3.13-rc2","v3.13-rc3","v3.13-rc4","v3.13-rc5","v3.13-rc6","v3.13-rc7","v3.13-rc8","v3.14","v3.14-rc1","v3.14-rc2","v3.14-rc3","v3.14-rc4","v3.14-rc5","v3.14-rc6","v3.14-rc7","v3.14-rc8","v3.15","v3.15-rc1","v3.15-rc2","v3.15-rc3","v3.15-rc4","v3.15-rc5","v3.15-rc6","v3.15-rc7","v3.15-rc8","v3.16","v3.16-rc1","v3.16-rc2","v3.16-rc3","v3.16-rc4","v3.16-rc5","v3.16-rc6","v3.16-rc7","v3.17","v3.17-rc1","v3.17-rc2","v3.17-rc3","v3.17-rc4","v3.17-rc5","v3.17-rc6","v3.17-rc7","v3.18","v3.18-rc1","v3.18-rc2","v3.18-rc3","v3.18-rc4","v3.18-rc5","v3.18-rc6","v3.18-r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