CVE-2025-40362

HIGH

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. N...

Affects 1 product across 7 vendors.

CVSS 3.18.8
EPSS0.2%
Percentile5th
PatchUnknown
CVSS Vector — Plain English Requires local access, low complexity, low privileges required, no user interaction needed, can impact systems beyond the vulnerable component, full confidentiality impact, full integrity impact, full availability impact.
◆ AI Analysis — automated analysis, not human-reviewed

A vulnerability in the Linux kernel's Ceph file system (multifs mds auth caps issue) could allow unauthorized access to file system resources in a multifs Ceph cluster by applying the mds auth caps of one file system to another.

BSID: BS-2025-GLOBAL-259157-I • Model: /workspace/models/qwen2.5-coder-32b-instruct-bf16 • Confidence: MEDIUM

Is this CVE in your environment?

BreachSpider monitors your ICS/OT environment for vulnerabilities like this one. No agents or network access required. Free to start.

Check My Environment →
Frequently Asked Questions
What is CVE-2025-40362?
A vulnerability in the Linux kernel's Ceph file system (multifs mds auth caps issue) could allow unauthorized access to file system resources in a multifs Ceph cluster by applying the mds auth caps of one file system to another.
What is the CVSS score for CVE-2025-40362?
CVE-2025-40362 has CVSS 8.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H. EPSS: 0.2%.
Is CVE-2025-40362 actively exploited?
No confirmed active exploitation of CVE-2025-40362 as of 2026-10-17.
How do I remediate CVE-2025-40362?
Priority: HIGH.
What systems are affected by CVE-2025-40362?
CVE-2025-40362 affects Associated; Ceph; Client; Echo; Fuse; Kernel; Linux Linux.
Vulnerability Details
CVE IDCVE-2025-40362
BSIDBS-2025-GLOBAL-259157-I BreachSpider Global ID
CVSS VectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Published2025-12-16
Last Modified2026-10-15
ICS Relevance0%
SourceNVD
Official 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" ]

Source: NIST NVD / MITRE CVE Database

Attack Vector Analysis — CITED Relevance

An attacker with access to one file system in a multifs Ceph cluster could potentially exploit this vulnerability to gain unauthorized access to resources in another file system within the same cluster, bypassing intended authentication controls.

Exploitation Likelihood: MEDIUM

Affected Products
VendorProductAffected Versions
Associated — —
Ceph — —
Client — —
Echo — —
Fuse — —
Kernel — —
Linux Linux 6.10
Remediation

No official vendor advisory link on record. See the CVE record →

Threat Intelligence
● Threat Intelligence Validated: October 2026 | Threat Age: 304 Days
CISA known-exploitedNot in KEV catalog
Public ExploitNot confirmed
PoC CodeNot confirmed
AI Enrichment Record — provenance & audit hash
Model/workspace/models/qwen2.5-coder-32b-instruct-bf16
ConfidenceMEDIUM
Enriched At2026-05-24
SHA-512 Audit Hash3bfb133c2538e1cfb5b50e6e1dd1e44e27fee260388e5ce9de61b78c25dd82b492eb29d5666e95345c9a6234375c4810ce8f86028cccdeb317c24afe2677f1ee
Related CVEs affecting Associated
CVE-2024-2086 10.0 The Integrate Google Drive – Browse, Upload, Download, Embed, Play, Share, Ga... CVE-2025-40914 9.8 Perl CryptX before version 0.087 contains a dependency that may be susceptibl... CVE-2026-5229 9.8 The Form Notify plugin for WordPress is vulnerable to Authentication Bypass i... CVE-2024-45337 9.1 Applications and libraries which misuse connection.serverAuthenticate (via ca... CVE-2025-40273 8.8 In the Linux kernel, the following vulnerability has been resolved: NFSD: fr...
View all Associated CVEs →

ICS/OT Vulnerability Intelligence for Your Environment

BreachSpider tracks 384,000+ CVEs and matches them to your ICS/OT assets by exact version, with AI analysis, NERC CIP mapping, and vendor PSIRT contacts.

Create a free account →