CVE-2026-74315

In the Linux kernel, the following vulnerability has been resolved: lockd: Avoid hashing uninitialized bytes in nlm4svc_lookup_file() file_hash() digests the first LOCKD_FH_HASH_SIZE bytes of nfs_fh.data when bucketing nlm_files[], independent of fh.size. Commit 3de744ee4e45 ("lockd: Use xdrgen XDR functions for the NLMv4 TEST procedure") set .pc_argzero to zero for the converted procedures and moved file-handle population into nlm4svc_lookup_file(), which copies only xdr_lock->fh.len bytes into lock->fh.data. When an NLMv4 client presents a file handle shorter than LOCKD_FH_HASH_SIZE, bytes fh.len..31 retain whatever the argument buffer held from an earlier request. The same wire handle then hashes to different buckets across calls; nlm_lookup_file() misses the existing nlm_file entry, and lock-state lookups fail. Zero only the tail bytes that file_hash() would otherwise consume. Handles of LOCKD_FH_HASH_SIZE or larger already populate every byte that file_hash() reads.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/686c2434f9f16b87aeed18d76cc562df9f2695ab
https://git.kernel.org/stable/c/6e4c62caecf792e8a15ad9bc7f371e57c17e3302

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-15 06:22

Updated : 2026-08-17 06:19

NVD link : CVE-2026-74315

Mitre link : CVE-2026-74315

CVE.ORG link : CVE-2026-74315

JSON object : View

Products Affected

No product.

CWE

No CWE.

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