CVE-2026-53026
NFSD: fix nfs4_file access extra count in nfsd4_add_rdaccess_to_wrdeleg
Description
In the Linux kernel, the following vulnerability has been resolved: NFSD: fix nfs4_file access extra count in nfsd4_add_rdaccess_to_wrdeleg In nfsd4_add_rdaccess_to_wrdeleg, if fp->fi_fds[O_RDONLY] is already set by another thread, __nfs4_file_get_access should not be called to increment the nfs4_file access count since that was already done by the thread that added READ access to the file. The extra fi_access count in nfs4_file can prevent the corresponding nfsd_file from being freed. When stopping nfs-server service, these extra access counts trigger a BUG in kmem_cache_destroy() that shows nfsd_file object remaining on __kmem_cache_shutdown. This problem can be reproduced by running the Git project's test suite over NFS.
INFO
Published Date :
June 24, 2026, 5:17 p.m.
Last Modified :
July 15, 2026, 2:37 p.m.
Remotely Exploit :
Yes !
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
Solution
- Apply the provided patch to the Linux kernel.
- Recompile the kernel with the fix.
- Restart the NFS service.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-53026.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-53026 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-53026
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-53026 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-53026 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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Initial Analysis by [email protected]
Jul. 15, 2026
Action Type Old Value New Value Added CWE NVD-CWE-noinfo Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.19:rc5:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.19:rc6:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.19:rc7:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.19:rc8:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.19:-:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.19.1 up to (excluding) 7.0.10 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.18.4 up to (excluding) 6.18.33 Added Reference Type kernel.org: https://git.kernel.org/stable/c/4584229395d0d65bd517780afe97ffea07cb2c3d Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/b48f44f36e6607b2f818560f19deb86b4a9c717b Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/b81572b073441dfd32213e41857676d0dbff4665 Types: Patch -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jun. 28, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jun. 24, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'c07dc84ed67c5a182273171639bacbbb87c12175', 'lessThan': '4584229395d0d65bd517780afe97ffea07cb2c3d', 'versionType': 'git'}, {'status': 'affected', 'version': '8072e34e1387d03102b788677d491e2bcceef6f5', 'lessThan': 'b81572b073441dfd32213e41857676d0dbff4665', 'versionType': 'git'}, {'status': 'affected', 'version': '8072e34e1387d03102b788677d491e2bcceef6f5', 'lessThan': 'b48f44f36e6607b2f818560f19deb86b4a9c717b', 'versionType': 'git'}, {'status': 'affected', 'version': '6.18.4', 'lessThan': '6.18.33', 'versionType': 'semver'}], 'programFiles': ['fs/nfsd/nfs4state.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.19'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.19', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.18.33', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.0.10', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['fs/nfsd/nfs4state.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: NFSD: fix nfs4_file access extra count in nfsd4_add_rdaccess_to_wrdeleg In nfsd4_add_rdaccess_to_wrdeleg, if fp->fi_fds[O_RDONLY] is already set by another thread, __nfs4_file_get_access should not be called to increment the nfs4_file access count since that was already done by the thread that added READ access to the file. The extra fi_access count in nfs4_file can prevent the corresponding nfsd_file from being freed. When stopping nfs-server service, these extra access counts trigger a BUG in kmem_cache_destroy() that shows nfsd_file object remaining on __kmem_cache_shutdown. This problem can be reproduced by running the Git project's test suite over NFS. Added Reference https://git.kernel.org/stable/c/4584229395d0d65bd517780afe97ffea07cb2c3d Added Reference https://git.kernel.org/stable/c/b48f44f36e6607b2f818560f19deb86b4a9c717b Added Reference https://git.kernel.org/stable/c/b81572b073441dfd32213e41857676d0dbff4665