CVE-2025-40212
published 2025-11-24CVE-2025-40212: In the Linux kernel, the following vulnerability has been resolved: nfsd: fix refcount leak in nfsd_set_fh_dentry() nfsd exports a "pseudo root filesystem"…
PriorityP354critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.40%
33.2th percentile
In the Linux kernel, the following vulnerability has been resolved:
nfsd: fix refcount leak in nfsd_set_fh_dentry()
nfsd exports a "pseudo root filesystem" which is used by NFSv4 to find
the various exported filesystems using LOOKUP requests from a known root
filehandle. NFSv3 uses the MOUNT protocol to find those exported
filesystems and so is not given access to the pseudo root filesystem.
If a v3 (or v2) client uses a filehandle from that filesystem,
nfsd_set_fh_dentry() will report an error, but still stores the export
in "struct svc_fh" even though it also drops the reference (exp_put()).
This means that when fh_put() is called an extra reference will be dropped
which can lead to use-after-free and possible denial of service.
Normal NFS usage will not provide a pseudo-root filehandle to a v3
client. This bug can only be triggered by the client synthesising an
incorrect filehandle.
To fix this we move the assignments to the svc_fh later, after all
possible error cases have been detected.
Affected
12 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.17.9-1 (forky) | linux 6.17.9-1 (forky) |
| linux | linux | — | — |
| linux | linux | >= ef7f6c4904d03ccd7478e1ac20ed75f79c4ac444 < b6bc86ce3944b10b9fc181fc00c1a520a20ed965 | b6bc86ce3944b10b9fc181fc00c1a520a20ed965 |
| linux | linux | >= ef7f6c4904d03ccd7478e1ac20ed75f79c4ac444 < c83d7365cec5eb5ebeeee2a72e29b4ca58a7e4c2 | c83d7365cec5eb5ebeeee2a72e29b4ca58a7e4c2 |
| linux | linux | >= ef7f6c4904d03ccd7478e1ac20ed75f79c4ac444 < 8a7348a9ed70bda1c1f51d3f1815bcbdf9f3b38c | 8a7348a9ed70bda1c1f51d3f1815bcbdf9f3b38c |
| linux | linux_kernel | >= 0 < 6.12.63-1 | 6.12.63-1 |
| linux | linux_kernel | >= 0 < 6.17.9-1 | 6.17.9-1 |
| linux | linux_kernel | >= 0 < 6.17.0-14.14 | 6.17.0-14.14 |
| linux | linux_kernel | >= 6.12.0 < 6.12.59 | 6.12.59 |
| linux | linux_kernel | >= 6.13.0 < 6.17.9 | 6.17.9 |
| ubuntu | linux-aws | — | — |
| ubuntu | linux-oracle | — | — |
CVSS provenance
nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
vendor_redhat5.3MEDIUM
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OSV
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- ACPI drivers;
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This update corrects flaws in the following subsystems:
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- RISC-V architecture;
- S390 architecture;
- Sun Sparc architecture;
- x86 architecture;
- Xtensa architecture;
- Block layer subsystem;
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- Drivers core;
- Network block device driver;
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Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Nios II architecture;
- PA-RISC architecture;
- RISC-V architecture;
- S390 architecture;
- Sun Sparc architecture;
- x86 architecture;
- Xtensa architecture;
- Block layer subsystem;
- Cryptographic API;
- Compute Acceleration Framework;
- ACPI drivers;
- Drivers core;
- Network block device driver;
- Bluetooth drivers;
- Bus devices;
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- Clock framework and drivers;
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- CPU frequency scaling framework;
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- Xtensa architecture;
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- Cryptographic API;
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- ACPI drivers;
- Drivers core;
- Network block device driver;
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- Xtensa architecture;
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OSV
nfsd: fix refcount leak in nfsd_set_fh_dentry()
osv·2025-11-24
CVE-2025-40212 nfsd: fix refcount leak in nfsd_set_fh_dentry()
nfsd: fix refcount leak in nfsd_set_fh_dentry()
In the Linux kernel, the following vulnerability has been resolved:
nfsd: fix refcount leak in nfsd_set_fh_dentry()
nfsd exports a "pseudo root filesystem" which is used by NFSv4 to find
the various exported filesystems using LOOKUP requests from a known root
filehandle. NFSv3 uses the MOUNT protocol to find those exported
filesystems and so is not given access to the pseudo root filesystem.
If a v3 (or v2) client uses a filehandle from that filesystem,
nfsd_set_fh_dentry() will report an error, but still stores the export
in "struct svc_fh" even though it also drops the reference (exp_put()).
This means that when fh_put() is called an extra reference will be dropped
which can lead to use-after-free and possible denial of service.
Normal
OSV
CVE-2025-40212: In the Linux kernel, the following vulnerability has been resolved: nfsd: fix refcount leak in nfsd_set_fh_dentry() nfsd exports a "pseudo root filesy
osv·2025-11-24
CVE-2025-40212 CVE-2025-40212: In the Linux kernel, the following vulnerability has been resolved: nfsd: fix refcount leak in nfsd_set_fh_dentry() nfsd exports a "pseudo root filesy
In the Linux kernel, the following vulnerability has been resolved: nfsd: fix refcount leak in nfsd_set_fh_dentry() nfsd exports a "pseudo root filesystem" which is used by NFSv4 to find the various exported filesystems using LOOKUP requests from a known root filehandle. NFSv3 uses the MOUNT protocol to find those exported filesystems and so is not given access to the pseudo root filesystem. If a v3 (or v2) client uses a filehandle from that filesystem, nfsd_set_fh_dentry() will report an error, but still stores the export in "struct svc_fh" even though it also drops the reference (exp_put()). This means that when fh_put() is called an extra reference will be dropped which can lead to use-after-free and possible denial of service. Normal NFS usage will not provide a pseudo-root filehandle
GHSA
GHSA-cjm8-jghh-jmq3: In the Linux kernel, the following vulnerability has been resolved:
nfsd: fix refcount leak in nfsd_set_fh_dentry()
nfsd exports a "pseudo root file
ghsa_unreviewed·2025-11-24
CVE-2025-40212 GHSA-cjm8-jghh-jmq3: In the Linux kernel, the following vulnerability has been resolved:
nfsd: fix refcount leak in nfsd_set_fh_dentry()
nfsd exports a "pseudo root file
In the Linux kernel, the following vulnerability has been resolved:
nfsd: fix refcount leak in nfsd_set_fh_dentry()
nfsd exports a "pseudo root filesystem" which is used by NFSv4 to find
the various exported filesystems using LOOKUP requests from a known root
filehandle. NFSv3 uses the MOUNT protocol to find those exported
filesystems and so is not given access to the pseudo root filesystem.
If a v3 (or v2) client uses a filehandle from that filesystem,
nfsd_set_fh_dentry() will report an error, but still stores the export
in "struct svc_fh" even though it also drops the reference (exp_put()).
This means that when fh_put() is called an extra reference will be dropped
which can lead to use-after-free and possible denial of service.
Normal NFS usage will not provide a pseudo-root filehan
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vendor_ubuntu·2026-02-24
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Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Nios II architecture;
- PA-RISC architecture;
- RISC-V architecture;
- S390 architecture;
- Sun Sparc architecture;
- x86 architecture;
- Xtensa architecture;
- Block layer subsystem;
- Cryptographic API;
- Compute Acceleration Framework;
- ACPI drivers;
- Drivers core;
- Network block device driver;
- Bluetooth drivers;
- Bus devices;
- Hardware random number generator core;
- Character device driver;
- Clock framework and drivers;
- Data acquisition framewor
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vendor_ubuntu·2026-02-17
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Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Nios II architecture;
- PA-RISC architecture;
- RISC-V architecture;
- S390 architecture;
- Sun Sparc architecture;
- x86 architecture;
- Xtensa architecture;
- Block layer subsystem;
- Cryptographic API;
- Compute Acceleration Framework;
- ACPI drivers;
- Drivers core;
- Network block device driver;
- Bluetooth drivers;
- Bus devices;
- Hardware random number generator core;
- Character device driver;
- Clock framework and drivers;
- Data acquisition framework and dr
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Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Nios II architecture;
- PA-RISC architecture;
- RISC-V architecture;
- S390 architecture;
- Sun Sparc architecture;
- x86 architecture;
- Xtensa architecture;
- Block layer subsystem;
- Cryptographic API;
- Compute Acceleration Framework;
- ACPI drivers;
- Drivers core;
- Network block device driver;
- Bluetooth drivers;
- Bus devices;
- Hardware random number generator core;
- Character device driver;
- Clock framework and drivers;
- Data acquisition framework
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vendor_ubuntu·2026-02-12
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Title: Linux kernel (GCP) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Nios II architecture;
- PA-RISC architecture;
- RISC-V architecture;
- S390 architecture;
- Sun Sparc architecture;
- x86 architecture;
- Xtensa architecture;
- Block layer subsystem;
- Cryptographic API;
- Compute Acceleration Framework;
- ACPI drivers;
- Drivers core;
- Network block device driver;
- Bluetooth drivers;
- Bus devices;
- Hardware random number generator core;
- Character device driver;
- Clock framework and drivers;
- Data acquisition framework
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vendor_ubuntu·2026-02-12
CVE-2025-40304 Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Nios II architecture;
- PA-RISC architecture;
- RISC-V architecture;
- S390 architecture;
- Sun Sparc architecture;
- x86 architecture;
- Xtensa architecture;
- Block layer subsystem;
- Cryptographic API;
- Compute Acceleration Framework;
- ACPI drivers;
- Drivers core;
- Network block device driver;
- Bluetooth drivers;
- Bus devices;
- Hardware random number generator core;
- Character device driver;
- Clock framework and drivers;
- Data acquisition framework and dr
Red Hat
kernel: nfsd: fix refcount leak in nfsd_set_fh_dentry()
vendor_redhat·2025-11-24·CVSS 5.3
CVE-2025-40212 [MEDIUM] CWE-772 kernel: nfsd: fix refcount leak in nfsd_set_fh_dentry()
kernel: nfsd: fix refcount leak in nfsd_set_fh_dentry()
In the Linux kernel, the following vulnerability has been resolved:
nfsd: fix refcount leak in nfsd_set_fh_dentry()
nfsd exports a "pseudo root filesystem" which is used by NFSv4 to find
the various exported filesystems using LOOKUP requests from a known root
filehandle. NFSv3 uses the MOUNT protocol to find those exported
filesystems and so is not given access to the pseudo root filesystem.
If a v3 (or v2) client uses a filehandle from that filesystem,
nfsd_set_fh_dentry() will report an error, but still stores the export
in "struct svc_fh" even though it also drops the reference (exp_put()).
This means that when fh_put() is called an extra reference will be dropped
which can lead to use-after-free and possible denial of service.
No
Debian
CVE-2025-40212: linux - In the Linux kernel, the following vulnerability has been resolved: nfsd: fix r...
vendor_debian·2025
CVE-2025-40212 [LOW] CVE-2025-40212: linux - In the Linux kernel, the following vulnerability has been resolved: nfsd: fix r...
In the Linux kernel, the following vulnerability has been resolved: nfsd: fix refcount leak in nfsd_set_fh_dentry() nfsd exports a "pseudo root filesystem" which is used by NFSv4 to find the various exported filesystems using LOOKUP requests from a known root filehandle. NFSv3 uses the MOUNT protocol to find those exported filesystems and so is not given access to the pseudo root filesystem. If a v3 (or v2) client uses a filehandle from that filesystem, nfsd_set_fh_dentry() will report an error, but still stores the export in "struct svc_fh" even though it also drops the reference (exp_put()). This means that when fh_put() is called an extra reference will be dropped which can lead to use-after-free and possible denial of service. Normal NFS usage will not provide a pseudo-root filehandle
No detection rules found.
No public exploits indexed.
2025-11-24
Published