cbcvebase.
CVE-2026-53391
published 2026-07-19

CVE-2026-53391: In the Linux kernel, the following vulnerability has been resolved: NFSv4/pNFS: reject zero-length r_addr in nfs4_decode_mp_ds_addr nfs4_decode_mp_ds_addr()…

PriorityP340high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.52%
41.1th percentile
In the Linux kernel, the following vulnerability has been resolved: NFSv4/pNFS: reject zero-length r_addr in nfs4_decode_mp_ds_addr nfs4_decode_mp_ds_addr() decodes the r_netid and r_addr opaques of a netaddr4 from a GETDEVICEINFO multipath-DS body, then immediately calls strrchr(buf, '.') to locate the port separator. Both decodes use xdr_stream_decode_string_dup(), and the current code checks only "nlen < 0" / "rlen < 0" before dereferencing the returned string. When the on-wire opaque has length zero, xdr_stream_decode_opaque_inline() returns 0 and xdr_stream_decode_string_dup() falls through to its "*str = NULL; return ret" tail, leaving buf NULL with a return value of 0. The "< 0" check does not catch this, and the next line is strrchr(NULL, '.'), a kernel NULL pointer dereference reachable from any pNFS-flexfile client mounted against a malicious or compromised metadata server. Reject the zero-length cases explicitly so the decoder fails with -EBADMSG (treated as a malformed GETDEVICEINFO body) instead of panicking the client.

Affected

15 ranges
VendorProductVersion rangeFixed in
linuxlinux
linuxlinux>= 6b7f3cf96364eaf597940cb5c68a682894829915 < 76b94cbd32aacf36a641956385a852635c6802b976b94cbd32aacf36a641956385a852635c6802b9
linuxlinux>= 6b7f3cf96364eaf597940cb5c68a682894829915 < c8e4e0c701d0192a2efb6df059c0f9e19678c23dc8e4e0c701d0192a2efb6df059c0f9e19678c23d
linuxlinux>= 6b7f3cf96364eaf597940cb5c68a682894829915 < 6c344fff2feff9d4d716d8e4ad40e9b5040ee5ea6c344fff2feff9d4d716d8e4ad40e9b5040ee5ea
linuxlinux>= 6b7f3cf96364eaf597940cb5c68a682894829915 < 427ab81a811dab4bca9d19f82eec5847ae42646e427ab81a811dab4bca9d19f82eec5847ae42646e
linuxlinux>= 6b7f3cf96364eaf597940cb5c68a682894829915 < 012d37a568bfbb2c9686f03ade75560bc7139956012d37a568bfbb2c9686f03ade75560bc7139956
linuxlinux>= 6b7f3cf96364eaf597940cb5c68a682894829915 < 30aae62e50b4e074a90a9a5e15246548fbdc118230aae62e50b4e074a90a9a5e15246548fbdc1182
linuxlinux>= 6b7f3cf96364eaf597940cb5c68a682894829915 < 41fe0f7b84f0cb822ae10ab08592996a592b2a2541fe0f7b84f0cb822ae10ab08592996a592b2a25
linuxlinux_kernel
linuxlinux_kernel>= 4.0 < 5.15.2115.15.211
linuxlinux_kernel>= 5.16 < 6.1.1776.1.177
linuxlinux_kernel>= 6.13 < 6.18.386.18.38
linuxlinux_kernel>= 6.19 < 7.1.37.1.3
linuxlinux_kernel>= 6.2 < 6.6.1446.6.144
linuxlinux_kernel>= 6.7 < 6.12.956.12.95

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
vendor_redhat7.5HIGH
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