CVE-2023-53606

Published Oct 4, 2025

Last updated 8 days ago

CVSS high 7.5

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: nfsd: clean up potential nfsd_file refcount leaks in COPY codepath There are two different flavors of the nfsd4_copy struct. One is embedded in the compound and is used directly in synchronous copies. The other is dynamically allocated, refcounted and tracked in the client struture. For the embedded one, the cleanup just involves releasing any nfsd_files held on its behalf. For the async one, the cleanup is a bit more involved, and we need to dequeue it from lists, unhash it, etc. There is at least one potential refcount leak in this code now. If the kthread_create call fails, then both the src and dst nfsd_files in the original nfsd4_copy object are leaked. The cleanup in this codepath is also sort of weird. In the async copy case, we'll have up to four nfsd_file references (src and dst for both flavors of copy structure). They are both put at the end of nfsd4_do_async_copy, even though the ones held on behalf of the embedded one outlive that structure. Change it so that we always clean up the nfsd_file refs held by the embedded copy structure before nfsd4_copy returns. Rework cleanup_async_copy to handle both inter and intra copies. Eliminate nfsd4_cleanup_intra_ssc since it now becomes a no-op.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
NVD-CWE-Other

Social media

Hype score
Not currently trending

  1. CVE-2023-53606 In the Linux kernel, the following vulnerability has been resolved: nfsd: clean up potential nfsd_file refcount leaks in COPY codepath There are two different flavo… https://t.co/wLig4Z8STI

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    4 Oct 2025

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Configurations

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References

Sources include official advisories and independent security research.