CVE-2025-68368
published 2025-12-24CVE-2025-68368: In the Linux kernel, the following vulnerability has been resolved: md: init bioset in mddev_init IO operations may be needed before md_run(), such as updating…
PriorityP419medium6.4
EPSS
0.15%
5.1th percentile
In the Linux kernel, the following vulnerability has been resolved:
md: init bioset in mddev_init
IO operations may be needed before md_run(), such as updating metadata
after writing sysfs. Without bioset, this triggers a NULL pointer
dereference as below:
BUG: kernel NULL pointer dereference, address: 0000000000000020
Call Trace:
md_update_sb+0x658/0xe00
new_level_store+0xc5/0x120
md_attr_store+0xc9/0x1e0
sysfs_kf_write+0x6f/0xa0
kernfs_fop_write_iter+0x141/0x2a0
vfs_write+0x1fc/0x5a0
ksys_write+0x79/0x180
__x64_sys_write+0x1d/0x30
x64_sys_call+0x2818/0x2880
do_syscall_64+0xa9/0x580
entry_SYSCALL_64_after_hwframe+0x4b/0x53
Reproducer
```
mdadm -CR /dev/md0 -l1 -n2 /dev/sd[cd]
echo inactive > /sys/block/md0/md/array_state
echo 10 > /sys/block/md0/md/new_level
```
mddev_init() can only be called once per mddev, no need to test if bioset
has been initialized anymore.
Affected
18 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.18.3-1 (forky) | linux 6.18.3-1 (forky) |
| linux | linux | — | — |
| linux | linux | >= d981ed8419303ed12351eea8541ad6cb76455fe3 < 9d37fe37dfa0833a8768740f0575e0ffd793cb4a | 9d37fe37dfa0833a8768740f0575e0ffd793cb4a |
| linux | linux | >= d981ed8419303ed12351eea8541ad6cb76455fe3 < 381a3ce1c0ffed647c9b913e142b099c7e9d5afc | 381a3ce1c0ffed647c9b913e142b099c7e9d5afc |
| linux | linux_kernel | >= 0 < 6.18.3-1 | 6.18.3-1 |
| linux | linux_kernel | >= 6.12.0 < 6.18.2 | 6.18.2 |
| ubuntu | linux-aws | — | — |
| ubuntu | linux-aws-6.17 | — | — |
| ubuntu | linux-azure | — | — |
| ubuntu | linux-azure-6.17 | — | — |
| ubuntu | linux-gcp | — | — |
| ubuntu | linux-gcp-6.17 | — | — |
| ubuntu | linux-hwe-6.17 | — | — |
| ubuntu | linux-oem-6.17 | — | — |
| ubuntu | linux-oracle | — | — |
| ubuntu | linux-oracle-6.17 | — | — |
| ubuntu | linux-raspi | — | — |
| ubuntu | linux-realtime-6.17 | — | — |
CVSS provenance
vendor_ubuntu6.4MEDIUM
vendor_redhat5.5MEDIUM
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OSV
CVE-2025-68368: In the Linux kernel, the following vulnerability has been resolved: md: init bioset in mddev_init IO operations may be needed before md_run(), such as
osv·2025-12-24
CVE-2025-68368 CVE-2025-68368: In the Linux kernel, the following vulnerability has been resolved: md: init bioset in mddev_init IO operations may be needed before md_run(), such as
In the Linux kernel, the following vulnerability has been resolved: md: init bioset in mddev_init IO operations may be needed before md_run(), such as updating metadata after writing sysfs. Without bioset, this triggers a NULL pointer dereference as below: BUG: kernel NULL pointer dereference, address: 0000000000000020 Call Trace: md_update_sb+0x658/0xe00 new_level_store+0xc5/0x120 md_attr_store+0xc9/0x1e0 sysfs_kf_write+0x6f/0xa0 kernfs_fop_write_iter+0x141/0x2a0 vfs_write+0x1fc/0x5a0 ksys_write+0x79/0x180 __x64_sys_write+0x1d/0x30 x64_sys_call+0x2818/0x2880 do_syscall_64+0xa9/0x580 entry_SYSCALL_64_after_hwframe+0x4b/0x53 Reproducer ``` mdadm -CR /dev/md0 -l1 -n2 /dev/sd[cd] echo inactive > /sys/block/md0/md/array_state echo 10 > /sys/block/md0/md/new_level ``` mddev_init() can only be c
OSV
md: init bioset in mddev_init
osv·2025-12-24
CVE-2025-68368 md: init bioset in mddev_init
md: init bioset in mddev_init
In the Linux kernel, the following vulnerability has been resolved:
md: init bioset in mddev_init
IO operations may be needed before md_run(), such as updating metadata
after writing sysfs. Without bioset, this triggers a NULL pointer
dereference as below:
BUG: kernel NULL pointer dereference, address: 0000000000000020
Call Trace:
md_update_sb+0x658/0xe00
new_level_store+0xc5/0x120
md_attr_store+0xc9/0x1e0
sysfs_kf_write+0x6f/0xa0
kernfs_fop_write_iter+0x141/0x2a0
vfs_write+0x1fc/0x5a0
ksys_write+0x79/0x180
__x64_sys_write+0x1d/0x30
x64_sys_call+0x2818/0x2880
do_syscall_64+0xa9/0x580
entry_SYSCALL_64_after_hwframe+0x4b/0x53
Reproducer
```
mdadm -CR /dev/md0 -l1 -n2 /dev/sd[cd]
echo inactive > /sys/block/md0/md/array_state
echo 10 > /sys/block/md0/md/new_l
GHSA
GHSA-8jvw-6j3w-p767: In the Linux kernel, the following vulnerability has been resolved:
md: init bioset in mddev_init
IO operations may be needed before md_run(), such
ghsa_unreviewed·2025-12-24
CVE-2025-68368 GHSA-8jvw-6j3w-p767: In the Linux kernel, the following vulnerability has been resolved:
md: init bioset in mddev_init
IO operations may be needed before md_run(), such
In the Linux kernel, the following vulnerability has been resolved:
md: init bioset in mddev_init
IO operations may be needed before md_run(), such as updating metadata
after writing sysfs. Without bioset, this triggers a NULL pointer
dereference as below:
BUG: kernel NULL pointer dereference, address: 0000000000000020
Call Trace:
md_update_sb+0x658/0xe00
new_level_store+0xc5/0x120
md_attr_store+0xc9/0x1e0
sysfs_kf_write+0x6f/0xa0
kernfs_fop_write_iter+0x141/0x2a0
vfs_write+0x1fc/0x5a0
ksys_write+0x79/0x180
__x64_sys_write+0x1d/0x30
x64_sys_call+0x2818/0x2880
do_syscall_64+0xa9/0x580
entry_SYSCALL_64_after_hwframe+0x4b/0x53
Reproducer
```
mdadm -CR /dev/md0 -l1 -n2 /dev/sd[cd]
echo inactive > /sys/block/md0/md/array_state
echo 10 > /sys/block/md0/md/new_level
```
mddev_init() can only
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-05-07·CVSS 6.4
CVE-2025-71149 [MEDIUM] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality. (CVE-2024-36347)
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:
- MIPS architecture;
- PowerPC architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI drivers;
-
Ubuntu
Linux kernel (Raspberry Pi) vulnerabilities
vendor_ubuntu·2026-05-07·CVSS 6.4
CVE-2025-68781 [MEDIUM] Linux kernel (Raspberry Pi) vulnerabilities
Title: Linux kernel (Raspberry Pi) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality. (CVE-2024-36347)
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:
- MIPS architecture;
- PowerPC architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
-
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-04-23·CVSS 6.4
CVE-2025-68801 [MEDIUM] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality.
(CVE-2024-36347)
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:
- MIPS architecture;
- PowerPC architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI drivers;
-
Ubuntu
Linux kernel (GCP) vulnerabilities
vendor_ubuntu·2026-04-17·CVSS 6.4
CVE-2025-68736 [MEDIUM] Linux kernel (GCP) vulnerabilities
Title: Linux kernel (GCP) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality.
(CVE-2024-36347)
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:
- MIPS architecture;
- PowerPC architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI driv
Ubuntu
Linux kernel (Real-time) vulnerabilities
vendor_ubuntu·2026-04-17·CVSS 6.4
CVE-2025-68736 [MEDIUM] Linux kernel (Real-time) vulnerabilities
Title: Linux kernel (Real-time) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality.
(CVE-2024-36347)
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:
- MIPS architecture;
- PowerPC architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACP
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-04-16·CVSS 6.4
CVE-2025-68736 [MEDIUM] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality.
(CVE-2024-36347)
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:
- MIPS architecture;
- PowerPC architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI drivers;
-
Red Hat
kernel: Kernel: Denial of Service in md driver via uninitialized bioset
vendor_redhat·2025-12-24·CVSS 5.5
CVE-2025-68368 [MEDIUM] CWE-476 kernel: Kernel: Denial of Service in md driver via uninitialized bioset
kernel: Kernel: Denial of Service in md driver via uninitialized bioset
In the Linux kernel, the following vulnerability has been resolved:
md: init bioset in mddev_init
IO operations may be needed before md_run(), such as updating metadata
after writing sysfs. Without bioset, this triggers a NULL pointer
dereference as below:
BUG: kernel NULL pointer dereference, address: 0000000000000020
Call Trace:
md_update_sb+0x658/0xe00
new_level_store+0xc5/0x120
md_attr_store+0xc9/0x1e0
sysfs_kf_write+0x6f/0xa0
kernfs_fop_write_iter+0x141/0x2a0
vfs_write+0x1fc/0x5a0
ksys_write+0x79/0x180
__x64_sys_write+0x1d/0x30
x64_sys_call+0x2818/0x2880
do_syscall_64+0xa9/0x580
entry_SYSCALL_64_after_hwframe+0x4b/0x53
Reproducer
```
mdadm -CR /dev/md0 -l1 -n2 /dev/sd[cd]
echo inactive > /sys/block/md0/md/array_s
Debian
CVE-2025-68368: linux - In the Linux kernel, the following vulnerability has been resolved: md: init bi...
vendor_debian·2025
CVE-2025-68368 [LOW] CVE-2025-68368: linux - In the Linux kernel, the following vulnerability has been resolved: md: init bi...
In the Linux kernel, the following vulnerability has been resolved: md: init bioset in mddev_init IO operations may be needed before md_run(), such as updating metadata after writing sysfs. Without bioset, this triggers a NULL pointer dereference as below: BUG: kernel NULL pointer dereference, address: 0000000000000020 Call Trace: md_update_sb+0x658/0xe00 new_level_store+0xc5/0x120 md_attr_store+0xc9/0x1e0 sysfs_kf_write+0x6f/0xa0 kernfs_fop_write_iter+0x141/0x2a0 vfs_write+0x1fc/0x5a0 ksys_write+0x79/0x180 __x64_sys_write+0x1d/0x30 x64_sys_call+0x2818/0x2880 do_syscall_64+0xa9/0x580 entry_SYSCALL_64_after_hwframe+0x4b/0x53 Reproducer ``` mdadm -CR /dev/md0 -l1 -n2 /dev/sd[cd] echo inactive > /sys/block/md0/md/array_state echo 10 > /sys/block/md0/md/new_level ``` mddev_init() can only be c
No detection rules found.
No public exploits indexed.
Wiz
CVE-2025-68368 Impact, Exploitability, and Mitigation Steps | Wiz
blogs_wiz
CVE-2025-68368 CVE-2025-68368 Impact, Exploitability, and Mitigation Steps | Wiz
## CVE-2025-68368 :
Linux Kernel vulnerability analysis and mitigation
In the Linux kernel, the following vulnerability has been resolved:
md: init bioset in mddev_init
IO operations may be needed before md_run(), such as updating metadata
after writing sysfs. Without bioset, this triggers a NULL pointer
dereference as below:
BUG: kernel NULL pointer dereference, address: 0000000000000020
Call Trace:
md_update_sb+0x658/0xe00
new_level_store+0xc5/0x120
md_attr_store+0xc9/0x1e0
sysfs_kf_write+0x6f/0xa0
kernfs_fop_write_iter+0x141/0x2a0
vfs_write+0x1fc/0x5a0
ksys_write+0x79/0x180
__x64_sys_write+0x1d/0x30
x64_sys_call+0x2818/0x2880
do_syscall_64+0xa9/0x580
entry_SYSCALL_64_after_hwframe+0x4b/0x53
Reproducer
mdadm -CR /dev/md0 -l1 -n2 /dev/sd[cd]
echo inactive > /sys/block/md0/md/array_
Bugzilla
CVE-2025-68368 kernel: Kernel: Denial of Service in md driver via uninitialized bioset
bugzilla·2025-12-24
CVE-2025-68368 [MEDIUM] CVE-2025-68368 kernel: Kernel: Denial of Service in md driver via uninitialized bioset
CVE-2025-68368 kernel: Kernel: Denial of Service in md driver via uninitialized bioset
In the Linux kernel, the following vulnerability has been resolved:
md: init bioset in mddev_init
IO operations may be needed before md_run(), such as updating metadata
after writing sysfs. Without bioset, this triggers a NULL pointer
dereference as below:
BUG: kernel NULL pointer dereference, address: 0000000000000020
Call Trace:
md_update_sb+0x658/0xe00
new_level_store+0xc5/0x120
md_attr_store+0xc9/0x1e0
sysfs_kf_write+0x6f/0xa0
kernfs_fop_write_iter+0x141/0x2a0
vfs_write+0x1fc/0x5a0
ksys_write+0x79/0x180
__x64_sys_write+0x1d/0x30
x64_sys_call+0x2818/0x2880
do_syscall_64+0xa9/0x580
entry_SYSCALL_64_after_hwframe+0x4b/0x53
Reproducer
```
mdadm -CR /dev/md0 -l1 -n2 /dev/sd[cd]
echo inactive > /sys/b
2025-12-24
Published