CVE-2026-46139

Source
https://cve.org/CVERecord?id=CVE-2026-46139
Import Source
https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-46139.json
JSON Data
https://api.test.osv.dev/v1/vulns/CVE-2026-46139
Downstream
BELL (1)
DEBIAN (1)
openSUSE (1)
ROOT (1)
SUSE (6)
UBUNTU (1)
Related
Published
2026-05-28T09:35:55Z
Modified
2026-11-13T04:04:19Z
Summary
smb: client: use kzalloc to zero-initialize security descriptor buffer
Details

In the Linux kernel, the following vulnerability has been resolved:

smb: client: use kzalloc to zero-initialize security descriptor buffer

Commit 62e7dd0a39c2d ("smb: common: change the data type of num_aces to le16") split struct smb_acl's __le32 num_aces field into __le16 num_aces and __le16 reserved. The reserved field corresponds to Sbz2 in the MS-DTYP ACL wire format, which must be zero [1].

When building an ACL descriptor in build_sec_desc(), we are using a kmalloc()'ed descriptor buffer and writing the fields explicitly using le16() writes now. This never writes to the 2 byte reserved field, leaving it as uninitialized heap data.

When the reserved field happens to contain non-zero slab garbage, Samba rejects the security descriptor with "ndr_pull_security_descriptor failed: Range Error", causing chmod to fail with EINVAL.

Change kmalloc() to kzalloc() to ensure the entire buffer is zero-initialized.

[1] https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-dtyp/20233ed8-a6c6-4097-aafa-dd545ed24428

Database specific
{
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46139.json"
}
References

Affected packages

Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Affected ranges

Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
1593ddb37bd124c131fe635397df68e854a03108
Fixed
4c3ed344a970aad51388ac3b0145b98318f0e21f
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
da087905e3270e2291c0afae39a28e7d183e5ec3
Fixed
941a1e6eb35440336913afc88a82103291956d5d
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
62e7dd0a39c2d0d7ff03274c36df971f1b3d2d0d
Fixed
be1ef9512a3f5a755895c24f31b334342f4aa15b
Fixed
9bdb2ca31368b7671949dfb94a5d57ffccd01edd
Fixed
5e489c6c47a2ac15edbaca153b9348e42c1eacab
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
191f2f444745087c3c51fd6042a0e25f42315ab0

Affected versions

v6.*
v6.12.23
v6.12.24
v6.12.25
v6.12.26
v6.12.27
v6.12.28
v6.12.29
v6.12.30
v6.12.31
v6.12.32
v6.12.33
v6.12.34
v6.12.35
v6.12.36
v6.12.37
v6.12.38
v6.12.39
v6.12.40
v6.12.41
v6.12.42
v6.12.43
v6.12.44
v6.12.45
v6.12.46
v6.12.47
v6.12.48
v6.12.49
v6.12.50
v6.12.51
v6.12.52
v6.12.53
v6.12.54
v6.12.55
v6.12.56
v6.12.57
v6.12.58
v6.12.59
v6.12.60
v6.12.61
v6.12.62
v6.12.63
v6.12.64
v6.12.65
v6.12.66
v6.12.67
v6.12.68
v6.12.69
v6.12.70
v6.12.71
v6.12.72
v6.12.73
v6.12.74
v6.12.75
v6.12.76
v6.12.77
v6.12.78
v6.12.79
v6.12.80
v6.12.81
v6.12.82
v6.12.83
v6.12.84
v6.12.85
v6.12.86
v6.12.87
v6.13.11
v6.13.12

Database specific

source
"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-46139.json"

Linux / Kernel

Package

Name
Kernel

Affected ranges

Type
ECOSYSTEM
Events
Introduced
6.12.23
Fixed
6.12.88
Type
ECOSYSTEM
Events
Introduced
6.13.11
Fixed
6.14
Type
ECOSYSTEM
Events
Introduced
6.14.0
Fixed
6.18.30
Type
ECOSYSTEM
Events
Introduced
6.19.0
Fixed
7.0.7

Database specific

source
"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-46139.json"