U.S. flag   An official website of the United States government
Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock (Dot gov) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

CVE-2025-40362 Detail

Description

In the Linux kernel, the following vulnerability has been resolved: ceph: fix multifs mds auth caps issue The mds auth caps check should also validate the fsname along with the associated caps. Not doing so would result in applying the mds auth caps of one fs on to the other fs in a multifs ceph cluster. The bug causes multiple issues w.r.t user authentication, following is one such example. Steps to Reproduce (on vstart cluster): 1. Create two file systems in a cluster, say 'fsname1' and 'fsname2' 2. Authorize read only permission to the user 'client.usr' on fs 'fsname1' $ceph fs authorize fsname1 client.usr / r 3. Authorize read and write permission to the same user 'client.usr' on fs 'fsname2' $ceph fs authorize fsname2 client.usr / rw 4. Update the keyring $ceph auth get client.usr >> ./keyring With above permssions for the user 'client.usr', following is the expectation. a. The 'client.usr' should be able to only read the contents and not allowed to create or delete files on file system 'fsname1'. b. The 'client.usr' should be able to read/write on file system 'fsname2'. But, with this bug, the 'client.usr' is allowed to read/write on file system 'fsname1'. See below. 5. Mount the file system 'fsname1' with the user 'client.usr' $sudo bin/mount.ceph [email protected]=/ /kmnt_fsname1_usr/ 6. Try creating a file on file system 'fsname1' with user 'client.usr'. This should fail but passes with this bug. $touch /kmnt_fsname1_usr/file1 7. Mount the file system 'fsname1' with the user 'client.admin' and create a file. $sudo bin/mount.ceph [email protected]=/ /kmnt_fsname1_admin $echo "data" > /kmnt_fsname1_admin/admin_file1 8. Try removing an existing file on file system 'fsname1' with the user 'client.usr'. This shoudn't succeed but succeeds with the bug. $rm -f /kmnt_fsname1_usr/admin_file1 For more information, please take a look at the corresponding mds/fuse patch and tests added by looking into the tracker mentioned below. v2: Fix a possible null dereference in doutc v3: Don't store fsname from mdsmap, validate against ceph_mount_options's fsname and use it v4: Code refactor, better warning message and fix possible compiler warning [ Slava.Dubeyko: "fsname check failed" -> "fsname mismatch" ]


Metrics

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

By selecting these links, you will be leaving NIST webspace. We have provided these links to other web sites because they may have information that would be of interest to you. No inferences should be drawn on account of other sites being referenced, or not, from this page. There may be other web sites that are more appropriate for your purpose. NIST does not necessarily endorse the views expressed, or concur with the facts presented on these sites. Further, NIST does not endorse any commercial products that may be mentioned on these sites. Please address comments about this page to [email protected].

URL Source(s) Tag(s)
https://git.kernel.org/stable/c/07640d34a781bb2e39020a39137073c03c4aa932 kernel.org
https://git.kernel.org/stable/c/22c73d52a6d05c5a2053385c0d6cd9984732799d kernel.org
https://git.kernel.org/stable/c/ca3da8b27ab9a0923ad477447cfb8fc7f4b4c523 kernel.org

Weakness Enumeration

CWE-ID CWE Name Source

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-40362
NVD Published Date:
12/16/2025
NVD Last Modified:
12/18/2025
Source:
kernel.org