CVE-2026-64391

CVE-2026-64391

Critical · published July 25, 2026

CVSS v3.1
9.8
EPSS
0%
Percentile
38.7
In the wild
Unconfirmed
What it is

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

ksmbd: use opener credentials for ADS I/O

Alternate data streams are stored as xattrs. Unlike regular file I/O,

their read and write paths therefore call VFS xattr helpers which recheck

inode permissions and LSM policy using the current task credentials.

Run ADS I/O with the credentials captured when the SMB handle was opened.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00457 · 38.7th percentile
Published
2026-07-25T14:17Z
Affected products (3)
ProductVersionsFixed in
linux/linux_kernel≥ 5.15, < 6.12.966.12.96
linux/linux_kernel≥ 6.13, < 6.18.396.18.39
linux/linux_kernel≥ 6.19, < 7.1.47.1.4
References (5)
https://git.kernel.org/stable/c/2ad5509dd576ae16d252d4698daf03002f9e0234 · 416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/2b4592cea214683de0f2ce6f8c22c097fb0ea1ab · 416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/52a56cf53ec834c44ac1b4d16d585f26613ee5ce · 416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/a8f5d39971bbad9340d49cd41b0e2da9452a649d · 416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/baa5e094886fffa7e6272edcb5e08be5ce28262c · 416baaa9-dc9f-4396-8d5f-8c081fb06d67
EPSS history
Timeline
  • 25 JUL 08:50Z
    ksmbd: use opener credentials for ADS I/O
    cvelistv5