NFSD: Hold net reference for the lifetime of /proc/fs/nfs/exports fd
Summary
| CVE | CVE-2026-31403 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-04-03 16:16:39 UTC |
| Updated | 2026-07-14 13:18:38 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: NFSD: Hold net reference for the lifetime of /proc/fs/nfs/exports fd The /proc/fs/nfs/exports proc entry is created at module init and persists for the module's lifetime. exports_proc_open() captures the caller's current network namespace and stores its svc_export_cache in seq->private, but takes no reference on the namespace. If the namespace is subsequently torn down (e.g. container destruction after the opener does setns() to a different namespace), nfsd_net_exit() calls nfsd_export_shutdown() which frees the cache. Subsequent reads on the still-open fd dereference the freed cache_detail, walking a freed hash table. Hold a reference on the struct net for the lifetime of the open file descriptor. This prevents nfsd_net_exit() from running -- and thus prevents nfsd_export_shutdown() from freeing the cache -- while any exports fd is open. cache_detail already stores its net pointer (cd->net, set by cache_create_net()), so exports_release() can retrieve it without additional per-file storage. |
Risk And Classification
Primary CVSS: v3.1 7.8 HIGH from 416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS: 0.000320000 probability, percentile 0.092090000 (date 2026-04-27)
Problem Types: NVD-CWE-noinfo
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | Secondary | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | CNA | DECLARED | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
CVSS v3.1 Breakdown
Attack Vector
LocalAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Operating System | Linux | Linux Kernel | All | All | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected 96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 76740c28050dc6db2f5550f1325b00a11bbb3255 git | Not specified |
| CNA | Linux | Linux | affected 96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 c7f406fb341d6747634b8b1fa5461656e5e56076 git | Not specified |
| CNA | Linux | Linux | affected 96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 d1a19217995df9c7e4118f5a2820c5032fef2945 git | Not specified |
| CNA | Linux | Linux | affected 96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 e3d77f935639e6ae4b381c80464c31df998d61f4 git | Not specified |
| CNA | Linux | Linux | affected 96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 db4a9f99b12a7ee1c19d86c83a3b752c7effa6c6 git | Not specified |
| CNA | Linux | Linux | affected 96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 6a8d70e2ad6aad2c345a5048edcb8168036f97d6 git | Not specified |
| CNA | Linux | Linux | affected 96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 e7fcf179b82d3a3730fd8615da01b087cc654d0b git | Not specified |
| CNA | Linux | Linux | affected 3.9 | Not specified |
| CNA | Linux | Linux | unaffected 3.9 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.10.253 5.10.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.167 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.130 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.78 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.20 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.19.10 6.19.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.0 * original_commit_for_fix | Not specified |
| ADP | Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP | affected V3.1.6 * custom | Not specified |
| ADP | Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP | affected V3.1.5 * custom | Not specified |
| ADP | Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP | affected V3.1.6 * custom | Not specified |
| ADP | Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP | affected V3.1.5 * custom | Not specified |
| ADP | Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP | affected V3.1.6 * custom | Not specified |
| ADP | Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP | affected V3.1.5 * custom | Not specified |
| ADP | Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP | affected V3.1.6 * custom | Not specified |
| ADP | Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP | affected V3.1.5 * custom | Not specified |
| ADP | Siemens | SIPLUS S7-1500 CPU 1518-4 PN/DP MFP | affected V3.1.6 * custom | Not specified |
| ADP | Siemens | SIPLUS S7-1500 CPU 1518-4 PN/DP MFP | affected V3.1.5 * custom | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/db4a9f99b12a7ee1c19d86c83a3b752c7effa6c6 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| cert-portal.siemens.com/productcert/html/ssa-082556.html | 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e | cert-portal.siemens.com | |
| git.kernel.org/stable/c/e3d77f935639e6ae4b381c80464c31df998d61f4 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/e7fcf179b82d3a3730fd8615da01b087cc654d0b | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| cert-portal.siemens.com/productcert/html/ssa-019113.html | 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e | cert-portal.siemens.com | |
| git.kernel.org/stable/c/c7f406fb341d6747634b8b1fa5461656e5e56076 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/6a8d70e2ad6aad2c345a5048edcb8168036f97d6 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/d1a19217995df9c7e4118f5a2820c5032fef2945 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/76740c28050dc6db2f5550f1325b00a11bbb3255 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.