cbcvebase.
CVE-2025-71090
published 2026-01-13

CVE-2025-71090: In the Linux kernel, the following vulnerability has been resolved: nfsd: fix nfsd_file reference leak in nfsd4_add_rdaccess_to_wrdeleg()…

PriorityP422medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.18%
7.9th percentile
In the Linux kernel, the following vulnerability has been resolved: nfsd: fix nfsd_file reference leak in nfsd4_add_rdaccess_to_wrdeleg() nfsd4_add_rdaccess_to_wrdeleg() unconditionally overwrites fp->fi_fds[O_RDONLY] with a newly acquired nfsd_file. However, if the client already has a SHARE_ACCESS_READ open from a previous OPEN operation, this action overwrites the existing pointer without releasing its reference, orphaning the previous reference. Additionally, the function originally stored the same nfsd_file pointer in both fp->fi_fds[O_RDONLY] and fp->fi_rdeleg_file with only a single reference. When put_deleg_file() runs, it clears fi_rdeleg_file and calls nfs4_file_put_access() to release the file. However, nfs4_file_put_access() only releases fi_fds[O_RDONLY] when the fi_access[O_RDONLY] counter drops to zero. If another READ open exists on the file, the counter remains elevated and the nfsd_file reference from the delegation is never released. This potentially causes open conflicts on that file. Then, on server shutdown, these leaks cause __nfsd_file_cache_purge() to encounter files with an elevated reference count that cannot be cleaned up, ultimately triggering a BUG() in kmem_cache_destroy() because there are still nfsd_file objects allocated in that cache.

Affected

31 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.18.5-1 (forky)linux 6.18.5-1 (forky)
linuxlinux
linuxlinux>= e7a8ebc305f26cab608e59a916a4ae89d6656c5f < c07dc84ed67c5a182273171639bacbbb87c12175c07dc84ed67c5a182273171639bacbbb87c12175
linuxlinux>= e7a8ebc305f26cab608e59a916a4ae89d6656c5f < 8072e34e1387d03102b788677d491e2bcceef6f58072e34e1387d03102b788677d491e2bcceef6f5
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.18.5-16.18.5-1
linuxlinux_kernel>= 6.17.0 < 6.18.46.18.4
linuxlinux_kernel>= 6.17.1 < 6.18.46.18.4
ubuntulinux
ubuntulinux-aws
ubuntulinux-aws-6.17
ubuntulinux-azure
ubuntulinux-azure-6.17
ubuntulinux-gcp
ubuntulinux-gcp-6.17
ubuntulinux-hwe-6.17
ubuntulinux-nvidia-6.17

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_ubuntu7.8HIGH
vendor_debian5.5LOW
vendor_redhat5.5MEDIUM
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