CVE-2026-53395
Received
Received - Intake
Linux kernel ACL Leak in nfsd4_create
Vulnerability report for CVE-2026-53395, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-07-19
Last updated on: 2026-07-19
Assigner: kernel.org
Description
Description
In the Linux kernel, the following vulnerability has been resolved:
nfsd: fix dead ACL conflict guard in nfsd4_create
nfsd4_create() steals create->cr_dpacl/cr_pacl into the local
nfsd_attrs via the designated initializer, then immediately sets the
source pointers to NULL. The subsequent conflict guard tests the
already-nilled source fields, making it permanently dead code:
if (create->cr_acl) {
if (create->cr_dpacl || create->cr_pacl) /* always false */
When a client encodes both FATTR4_WORD0_ACL and
FATTR4_WORD2_POSIX_{DEFAULT,ACCESS}_ACL in the same CREATE fattr
bitmap, nfsd4_acl_to_attr() overwrites attrs.na_pacl/na_dpacl without
releasing the originals, leaking two posix_acl slab objects per
request. Repeated requests cause unbounded slab exhaustion.
Fix by checking attrs.na_dpacl/na_pacl (the stolen values) instead of
the nilled create->cr_dpacl/cr_pacl, matching the correct pattern
already used in nfsd4_setattr().
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | * |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
