CVE-2026-43402
published 2026-05-08CVE-2026-43402: In the Linux kernel, the following vulnerability has been resolved: kthread: consolidate kthread exit paths to prevent use-after-free Guillaume reported…
PriorityP349critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.46%
36.8th percentile
In the Linux kernel, the following vulnerability has been resolved:
kthread: consolidate kthread exit paths to prevent use-after-free
Guillaume reported crashes via corrupted RCU callback function pointers
during KUnit testing. The crash was traced back to the pidfs rhashtable
conversion which replaced the 24-byte rb_node with an 8-byte rhash_head
in struct pid, shrinking it from 160 to 144 bytes.
struct kthread (without CONFIG_BLK_CGROUP) is also 144 bytes. With
CONFIG_SLAB_MERGE_DEFAULT and SLAB_HWCACHE_ALIGN both round up to
192 bytes and share the same slab cache. struct pid.rcu.func and
struct kthread.affinity_node both sit at offset 0x78.
When a kthread exits via make_task_dead() it bypasses kthread_exit() and
misses the affinity_node cleanup. free_kthread_struct() frees the memory
while the node is still linked into the global kthread_affinity_list. A
subsequent list_del() by another kthread writes through dangling list
pointers into the freed and reused memory, corrupting the pid's
rcu.func pointer.
Instead of patching free_kthread_struct() to handle the missed cleanup,
consolidate all kthread exit paths. Turn kthread_exit() into a macro
that calls do_exit() and add kthread_do_exit() which is called from
do_exit() for any task with PF_KTHREAD set. This guarantees that
kthread-specific cleanup always happens regardless of the exit path -
make_task_dead(), direct do_exit(), or kthread_exit().
Replace __to_kthread() with a new tsk_is_kthread() accessor in the
public header. Export do_exit() since module code using the
kthread_exit() macro now needs it directly.
Affected
13 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| linux | linux | — | — |
| linux | linux | >= 4d13f4304fa43471bfea101658a11feec7b28ac0 < 4729c7b00a347fd37d0cbc265b85f2884c3e06b6 | 4729c7b00a347fd37d0cbc265b85f2884c3e06b6 |
| linux | linux | >= 4d13f4304fa43471bfea101658a11feec7b28ac0 < 5a591d7a5e48d30100943940a30a6ab41b15c672 | 5a591d7a5e48d30100943940a30a6ab41b15c672 |
| linux | linux | >= 4d13f4304fa43471bfea101658a11feec7b28ac0 < 28aaa9c39945b7925a1cc1d513c8f21ed38f5e4f | 28aaa9c39945b7925a1cc1d513c8f21ed38f5e4f |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 6.14 < 6.18.19 | 6.18.19 |
| linux | linux_kernel | >= 6.19 < 6.19.9 | 6.19.9 |
| ubuntu | linux | — | — |
| ubuntu | linux-hwe-6.17 | — | — |
| ubuntu | linux-nvidia-6.17 | — | — |
| ubuntu | linux-oem-6.17 | — | — |
| ubuntu | linux-raspi | — | — |
CVSS provenance
nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
vendor_ubuntu7.1HIGH
vendor_redhat7.0MEDIUM
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VulDB
Linux Kernel up to 6.18.18/6.19.8 RCU Call make_task_dead use after free (Nessus ID 313433)
vuldb·2026-05-22·CVSS 9.8
CVE-2026-43402 [CRITICAL] Linux Kernel up to 6.18.18/6.19.8 RCU Call make_task_dead use after free (Nessus ID 313433)
A vulnerability identified as critical has been detected in Linux Kernel up to 6.18.18/6.19.8. This issue affects the function make_task_dead of the component RCU Call Handler. This manipulation causes use after free.
This vulnerability is registered as CVE-2026-43402. The attack requires access to the local network. No exploit is available.
You should upgrade the affected component.
GHSA
GHSA-v6fj-q6v9-3hmm: In the Linux kernel, the following vulnerability has been resolved:
kthread: consolidate kthread exit paths to prevent use-after-free
Guillaume repo
ghsa_unreviewed·2026-05-08
CVE-2026-43402 GHSA-v6fj-q6v9-3hmm: In the Linux kernel, the following vulnerability has been resolved:
kthread: consolidate kthread exit paths to prevent use-after-free
Guillaume repo
In the Linux kernel, the following vulnerability has been resolved:
kthread: consolidate kthread exit paths to prevent use-after-free
Guillaume reported crashes via corrupted RCU callback function pointers
during KUnit testing. The crash was traced back to the pidfs rhashtable
conversion which replaced the 24-byte rb_node with an 8-byte rhash_head
in struct pid, shrinking it from 160 to 144 bytes.
struct kthread (without CONFIG_BLK_CGROUP) is also 144 bytes. With
CONFIG_SLAB_MERGE_DEFAULT and SLAB_HWCACHE_ALIGN both round up to
192 bytes and share the same slab cache. struct pid.rcu.func and
struct kthread.affinity_node both sit at offset 0x78.
When a kthread exits via make_task_dead() it bypasses kthread_exit() and
misses the affinity_node cleanup. free_kthread_struct() frees the memo
Ubuntu
Linux kernel (Raspberry Pi) vulnerabilities
vendor_ubuntu·2026-07-15·CVSS 7.1
CVE-2026-31682 [HIGH] Linux kernel (Raspberry Pi) vulnerabilities
Title: Linux kernel (Raspberry Pi) 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;
- Block layer subsystem;
- Cryptographic API;
- DMA engine subsystem;
- InfiniBand drivers;
- STMicroelectronics network drivers;
- Network drivers;
- NVME drivers;
- SCSI subsystem;
- USB over IP driver;
- File systems infrastructure;
- Ext4 file system;
- Network file system (NFS) server daemon;
- SMB network file system;
- Kernel thread helper (kthread);
- IPv6 networking;
- Tracing infrastructure;
- Kernel exit() syscall;
- Scatterlist API;
- B.A.T.M.A.N. meshing protocol
Ubuntu
Linux kernel (HWE) vulnerabilities
vendor_ubuntu·2026-07-15·CVSS 7.1
CVE-2026-43341 [HIGH] Linux kernel (HWE) vulnerabilities
Title: Linux kernel (HWE) 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;
- Block layer subsystem;
- Cryptographic API;
- DMA engine subsystem;
- InfiniBand drivers;
- STMicroelectronics network drivers;
- Network drivers;
- NVME drivers;
- SCSI subsystem;
- USB over IP driver;
- File systems infrastructure;
- Ext4 file system;
- Network file system (NFS) server daemon;
- SMB network file system;
- Kernel thread helper (kthread);
- IPv6 networking;
- Tracing infrastructure;
- Kernel exit() syscall;
- Scatterlist API;
- B.A.T.M.A.N. meshing protocol;
- Ether
Ubuntu
Linux kernel (Raspberry Pi) vulnerabilities
vendor_ubuntu·2026-07-09·CVSS 7.1
CVE-2026-43341 [HIGH] Linux kernel (Raspberry Pi) vulnerabilities
Title: Linux kernel (Raspberry Pi) 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;
- Block layer subsystem;
- Cryptographic API;
- DMA engine subsystem;
- InfiniBand drivers;
- STMicroelectronics network drivers;
- Network drivers;
- NVME drivers;
- SCSI subsystem;
- USB over IP driver;
- File systems infrastructure;
- Ext4 file system;
- Network file system (NFS) server daemon;
- SMB network file system;
- Kernel thread helper (kthread);
- IPv6 networking;
- Tracing infrastructure;
- Kernel exit() syscall;
- Scatterlist API;
- B.A.T.M.A.N. meshing protocol
Ubuntu
Linux kernel (NVIDIA) vulnerabilities
vendor_ubuntu·2026-07-06·CVSS 5.5
CVE-2026-46325 [MEDIUM] Linux kernel (NVIDIA) vulnerabilities
Title: Linux kernel (NVIDIA) 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;
- S390 architecture;
- Block layer subsystem;
- Cryptographic API;
- DMA engine subsystem;
- GPU drivers;
- InfiniBand drivers;
- Ethernet bonding driver;
- STMicroelectronics network drivers;
- Network drivers;
- NVME drivers;
- SCSI subsystem;
- USB over IP driver;
- File systems infrastructure;
- Ext4 file system;
- Network file system (NFS) server daemon;
- SMB network file system;
- Kernel thread helper (kthread);
- Distributed Switch Architecture;
- IPv6 networking;
- Netfilt
Ubuntu
Linux kernel (OEM) vulnerabilities
vendor_ubuntu·2026-07-01·CVSS 7.1
CVE-2026-43304 [HIGH] Linux kernel (OEM) vulnerabilities
Title: Linux kernel (OEM) 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;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- DMA engine subsystem;
- InfiniBand drivers;
- STMicroelectronics network drivers;
- Network drivers;
- NVME drivers;
- SCSI subsystem;
- USB over IP driver;
- File systems infrastructure;
- Ext4 file system;
- Network file system (NFS) server daemon;
- SMB network file system;
- Kernel thread helper (kthread);
- IPv6 networking;
- Tracing infrastructure;
- Kernel exit() syscall;
- Scatterlist API;
- B.A.T.M.A.N. meshi
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-07-01·CVSS 7.1
CVE-2026-43304 [HIGH] 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;
- Block layer subsystem;
- Cryptographic API;
- DMA engine subsystem;
- InfiniBand drivers;
- STMicroelectronics network drivers;
- Network drivers;
- NVME drivers;
- SCSI subsystem;
- USB over IP driver;
- File systems infrastructure;
- Ext4 file system;
- Network file system (NFS) server daemon;
- SMB network file system;
- Kernel thread helper (kthread);
- IPv6 networking;
- Tracing infrastructure;
- Kernel exit() syscall;
- Scatterlist API;
- B.A.T.M.A.N. meshing protocol;
- Ethernet br
Red Hat
kernel: kthread: consolidate kthread exit paths to prevent use-after-free
vendor_redhat·2026-05-08·CVSS 7.0
CVE-2026-43402 [MEDIUM] CWE-825 kernel: kthread: consolidate kthread exit paths to prevent use-after-free
kernel: kthread: consolidate kthread exit paths to prevent use-after-free
A flaw was found in the Linux kernel. A vulnerability in the kernel thread (kthread) exit process can lead to a use-after-free condition. This occurs when a kthread exits without proper cleanup, allowing other kernel operations to access and corrupt previously freed memory. This can result in system instability and crashes.
Package: kernel (Red Hat Enterprise Linux 10) - Affected
Package: kernel (Red Hat Enterprise Linux 6) - Out of support scope
Package: kernel (Red Hat Enterprise Linux 7) - Not affected
Package: kernel-rt (Red Hat Enterprise Linux 7) - Not affected
Package: kernel (Red Hat Enterprise Linux 8) - Not affected
Package: kernel-rt (Red Hat Enterprise Linux 8) - Not affected
Package: kernel (Red
No detection rules found.
No public exploits indexed.
2026-05-08
Published