CVE-2023-54276
published 2025-12-30CVE-2023-54276: In the Linux kernel, the following vulnerability has been resolved: nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net Commit…
PriorityP423medium5.8
EPSS
0.17%
7.1th percentile
In the Linux kernel, the following vulnerability has been resolved:
nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net
Commit f5f9d4a314da ("nfsd: move reply cache initialization into nfsd
startup") moved the initialization of the reply cache into nfsd startup,
but didn't account for the stats counters, which can be accessed before
nfsd is ever started. The result can be a NULL pointer dereference when
someone accesses /proc/fs/nfsd/reply_cache_stats while nfsd is still
shut down.
This is a regression and a user-triggerable oops in the right situation:
- non-x86_64 arch
- /proc/fs/nfsd is mounted in the namespace
- nfsd is not started in the namespace
- unprivileged user calls "cat /proc/fs/nfsd/reply_cache_stats"
Although this is easy to trigger on some arches (like aarch64), on
x86_64, calling this_cpu_ptr(NULL) evidently returns a pointer to the
fixed_percpu_data. That struct looks just enough like a newly
initialized percpu var to allow nfsd_reply_cache_stats_show to access
it without Oopsing.
Move the initialization of the per-net+per-cpu reply-cache counters
back into nfsd_init_net, while leaving the rest of the reply cache
allocations to be done at nfsd startup time.
Kudos to Eirik who did most of the legwork to track this down.
Affected
10 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.4.4-1 (forky) | linux 6.4.4-1 (forky) |
| linux | linux | — | — |
| linux | linux | >= 4e18b58b106e34ac69d3052dd91f520bd83cf2fc < 3025d489f9c8984d1bf5916c4a20097ed80fca5c | 3025d489f9c8984d1bf5916c4a20097ed80fca5c |
| linux | linux | >= 70fdee548c036c6bdb496f284c9e78f1654b6dd0 < 8549384d0f65981761fe2077d04fa2a8d37b54e0 | 8549384d0f65981761fe2077d04fa2a8d37b54e0 |
| linux | linux | >= e7e571ed4ec7bb50136233d8e7b986efef2af8c1 < 66a178177b2b3bb1d71e854c5e7bbb320eb0e566 | 66a178177b2b3bb1d71e854c5e7bbb320eb0e566 |
| linux | linux | >= f5f9d4a314da88c0a5faa6d168bf69081b7a25ae < 768c408594b52d8531e1a8ab62e5620c19213e73 | 768c408594b52d8531e1a8ab62e5620c19213e73 |
| linux | linux | >= f5f9d4a314da88c0a5faa6d168bf69081b7a25ae < ed9ab7346e908496816cffdecd46932035f66e2e | ed9ab7346e908496816cffdecd46932035f66e2e |
| linux | linux_kernel | >= 0 < 6.4.4-1 | 6.4.4-1 |
| linux | linux_kernel | >= 0 < 6.4.4-1 | 6.4.4-1 |
| linux | linux_kernel | >= 6.3.0 < 6.4.4 | 6.4.4 |
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Red Hat
kernel: nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net
vendor_redhat·2025-12-30·CVSS 5.8
CVE-2023-54276 [MEDIUM] CWE-665 kernel: nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net
kernel: nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net
In the Linux kernel, the following vulnerability has been resolved:
nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net
Commit f5f9d4a314da ("nfsd: move reply cache initialization into nfsd
startup") moved the initialization of the reply cache into nfsd startup,
but didn't account for the stats counters, which can be accessed before
nfsd is ever started. The result can be a NULL pointer dereference when
someone accesses /proc/fs/nfsd/reply_cache_stats while nfsd is still
shut down.
This is a regression and a user-triggerable oops in the right situation:
- non-x86_64 arch
- /proc/fs/nfsd is mounted in the namespace
- nfsd is not started in the namespace
- unprivileged user calls "cat /
Debian
CVE-2023-54276: linux - In the Linux kernel, the following vulnerability has been resolved: nfsd: move ...
vendor_debian·2023
CVE-2023-54276 [LOW] CVE-2023-54276: linux - In the Linux kernel, the following vulnerability has been resolved: nfsd: move ...
In the Linux kernel, the following vulnerability has been resolved: nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net Commit f5f9d4a314da ("nfsd: move reply cache initialization into nfsd startup") moved the initialization of the reply cache into nfsd startup, but didn't account for the stats counters, which can be accessed before nfsd is ever started. The result can be a NULL pointer dereference when someone accesses /proc/fs/nfsd/reply_cache_stats while nfsd is still shut down. This is a regression and a user-triggerable oops in the right situation: - non-x86_64 arch - /proc/fs/nfsd is mounted in the namespace - nfsd is not started in the namespace - unprivileged user calls "cat /proc/fs/nfsd/reply_cache_stats" Although this is easy to trigger on some arches (lik
OSV
nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net
osv·2025-12-30
CVE-2023-54276 nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net
nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net
In the Linux kernel, the following vulnerability has been resolved:
nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net
Commit f5f9d4a314da ("nfsd: move reply cache initialization into nfsd
startup") moved the initialization of the reply cache into nfsd startup,
but didn't account for the stats counters, which can be accessed before
nfsd is ever started. The result can be a NULL pointer dereference when
someone accesses /proc/fs/nfsd/reply_cache_stats while nfsd is still
shut down.
This is a regression and a user-triggerable oops in the right situation:
- non-x86_64 arch
- /proc/fs/nfsd is mounted in the namespace
- nfsd is not started in the namespace
- unprivileged user calls "cat /proc
GHSA
GHSA-4hqq-5h4g-jhph: In the Linux kernel, the following vulnerability has been resolved:
nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net
Commi
ghsa_unreviewed·2025-12-30
CVE-2023-54276 GHSA-4hqq-5h4g-jhph: In the Linux kernel, the following vulnerability has been resolved:
nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net
Commi
In the Linux kernel, the following vulnerability has been resolved:
nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net
Commit f5f9d4a314da ("nfsd: move reply cache initialization into nfsd
startup") moved the initialization of the reply cache into nfsd startup,
but didn't account for the stats counters, which can be accessed before
nfsd is ever started. The result can be a NULL pointer dereference when
someone accesses /proc/fs/nfsd/reply_cache_stats while nfsd is still
shut down.
This is a regression and a user-triggerable oops in the right situation:
- non-x86_64 arch
- /proc/fs/nfsd is mounted in the namespace
- nfsd is not started in the namespace
- unprivileged user calls "cat /proc/fs/nfsd/reply_cache_stats"
Although this is easy to trigger on some arches
OSV
CVE-2023-54276: In the Linux kernel, the following vulnerability has been resolved: nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net Commit
osv·2025-12-30
CVE-2023-54276 CVE-2023-54276: In the Linux kernel, the following vulnerability has been resolved: nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net Commit
In the Linux kernel, the following vulnerability has been resolved: nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net Commit f5f9d4a314da ("nfsd: move reply cache initialization into nfsd startup") moved the initialization of the reply cache into nfsd startup, but didn't account for the stats counters, which can be accessed before nfsd is ever started. The result can be a NULL pointer dereference when someone accesses /proc/fs/nfsd/reply_cache_stats while nfsd is still shut down. This is a regression and a user-triggerable oops in the right situation: - non-x86_64 arch - /proc/fs/nfsd is mounted in the namespace - nfsd is not started in the namespace - unprivileged user calls "cat /proc/fs/nfsd/reply_cache_stats" Although this is easy to trigger on some arches (lik
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2023-54276 kernel: nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net
bugzilla·2025-12-30
CVE-2023-54276 [MEDIUM] CVE-2023-54276 kernel: nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net
CVE-2023-54276 kernel: nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net
In the Linux kernel, the following vulnerability has been resolved:
nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net
Commit f5f9d4a314da ("nfsd: move reply cache initialization into nfsd
startup") moved the initialization of the reply cache into nfsd startup,
but didn't account for the stats counters, which can be accessed before
nfsd is ever started. The result can be a NULL pointer dereference when
someone accesses /proc/fs/nfsd/reply_cache_stats while nfsd is still
shut down.
This is a regression and a user-triggerable oops in the right situation:
- non-x86_64 arch
- /proc/fs/nfsd is mounted in the namespace
- nfsd is not started in the namespace
- unprivilege
Wiz
CVE-2023-54276 Impact, Exploitability, and Mitigation Steps | Wiz
blogs_wiz
CVE-2023-54276 CVE-2023-54276 Impact, Exploitability, and Mitigation Steps | Wiz
## CVE-2023-54276 :
Linux Kernel vulnerability analysis and mitigation
In the Linux kernel, the following vulnerability has been resolved:
nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net
Commit f5f9d4a314da ("nfsd: move reply cache initialization into nfsd
startup") moved the initialization of the reply cache into nfsd startup,
but didn't account for the stats counters, which can be accessed before
nfsd is ever started. The result can be a NULL pointer dereference when
someone accesses /proc/fs/nfsd/reply_cache_stats while nfsd is still
shut down.
This is a regression and a user-triggerable oops in the right situation:
non-x86_64 arch
/proc/fs/nfsd is mounted in the namespace
nfsd is not started in the namespace
unprivileged user calls "cat /proc/fs/nfsd
https://git.kernel.org/stable/c/3025d489f9c8984d1bf5916c4a20097ed80fca5chttps://git.kernel.org/stable/c/66a178177b2b3bb1d71e854c5e7bbb320eb0e566https://git.kernel.org/stable/c/768c408594b52d8531e1a8ab62e5620c19213e73https://git.kernel.org/stable/c/8549384d0f65981761fe2077d04fa2a8d37b54e0https://git.kernel.org/stable/c/ed9ab7346e908496816cffdecd46932035f66e2e
2025-12-30
Published