Vulnerability-Lookup

FKIE_CVE-2026-31403

Vulnerability from fkie_nvd - Published: 2026-04-03 16:16 - Updated: 2026-05-20 12:15

Severity

7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Summary

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.

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/6a8d70e2ad6aad2c345a5048edcb8168036f97d6	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/76740c28050dc6db2f5550f1325b00a11bbb3255	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/c7f406fb341d6747634b8b1fa5461656e5e56076	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/d1a19217995df9c7e4118f5a2820c5032fef2945	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/db4a9f99b12a7ee1c19d86c83a3b752c7effa6c6	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/e3d77f935639e6ae4b381c80464c31df998d61f4	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/e7fcf179b82d3a3730fd8615da01b087cc654d0b	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0

JSON

To clipboard

{
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    }
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          "confidentialityImpact": "HIGH",
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          "privilegesRequired": "LOW",
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      "source": "nvd@nist.gov",
      "type": "Primary"
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  ]
}

CVE-2026-31403 (GCVE-0-2026-31403)

Vulnerability from cvelistv5 – Published: 2026-04-03 15:16 – Updated: 2026-05-11 22:08

Title

NFSD: Hold net reference for the lifetime of /proc/fs/nfs/exports fd

Summary

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Assigner

Linux

References

7 references

URL	Tags
https://git.kernel.org/stable/c/76740c28050dc6db2…
https://git.kernel.org/stable/c/c7f406fb341d67476…
https://git.kernel.org/stable/c/d1a19217995df9c7e…
https://git.kernel.org/stable/c/e3d77f935639e6ae4…
https://git.kernel.org/stable/c/db4a9f99b12a7ee1c…
https://git.kernel.org/stable/c/6a8d70e2ad6aad2c3…
https://git.kernel.org/stable/c/e7fcf179b82d3a373…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 , < 76740c28050dc6db2f5550f1325b00a11bbb3255 (git) Affected: 96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 , < c7f406fb341d6747634b8b1fa5461656e5e56076 (git) Affected: 96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 , < d1a19217995df9c7e4118f5a2820c5032fef2945 (git) Affected: 96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 , < e3d77f935639e6ae4b381c80464c31df998d61f4 (git) Affected: 96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 , < db4a9f99b12a7ee1c19d86c83a3b752c7effa6c6 (git) Affected: 96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 , < 6a8d70e2ad6aad2c345a5048edcb8168036f97d6 (git) Affected: 96d851c4d28de8cc83fe2bd5c6bc2eb8f253a6c5 , < e7fcf179b82d3a3730fd8615da01b087cc654d0b (git)
Linux	Linux	Affected: 3.9 Unaffected: 0 , < 3.9 (semver) Unaffected: 5.10.253 , ≤ 5.10.* (semver) Unaffected: 6.1.167 , ≤ 6.1.* (semver) Unaffected: 6.6.130 , ≤ 6.6.* (semver) Unaffected: 6.12.78 , ≤ 6.12.* (semver) Unaffected: 6.18.20 , ≤ 6.18.* (semver) Unaffected: 6.19.10 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

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          "programFiles": [
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}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

FKIE_CVE-2026-31403

CVE-2026-31403 (GCVE-0-2026-31403)

Tags

Sightings

Nomenclature