Linux Kernel up to 6.0.6 kernfs_remove_by_name_ns use after free

| CVSS Meta Temp Score | Current Exploit Price (≈) | CTI Interest Score |
|---|---|---|
| 7.7 | $0-$5k | 0.00 |
Summary
A vulnerability labeled as critical has been found in Linux Kernel up to 6.0.6. This affects the function kernfs_remove_by_name_ns. The manipulation results in use after free.
This vulnerability is reported as CVE-2022-50432. No exploit exists.
The affected component should be upgraded.
Details
A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.0.6. Affected is the function kernfs_remove_by_name_ns. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:
In the Linux kernel, the following vulnerability has been resolved: kernfs: fix use-after-free in __kernfs_remove Syzkaller managed to trigger concurrent calls to kernfs_remove_by_name_ns() for the same file resulting in a KASAN detected use-after-free. The race occurs when the root node is freed during kernfs_drain(). To prevent this acquire an additional reference for the root of the tree that is removed before calling __kernfs_remove(). Found by syzkaller with the following reproducer (slab_nomerge is required): syz_mount_image$ext4(0x0, &(0x7f0000000100)='./file0\x00', 0x100000, 0x0, 0x0, 0x0, 0x0) r0 = openat(0xffffffffffffff9c, &(0x7f0000000080)='/proc/self/exe\x00', 0x0, 0x0) close(r0) pipe2(&(0x7f0000000140)={0xffffffffffffffff, <r1=>0xffffffffffffffff}, 0x800) mount$9p_fd(0x0, &(0x7f0000000040)='./file0\x00', &(0x7f00000000c0), 0x408, &(0x7f0000000280)={'trans=fd,', {'rfdno', 0x3d, r0}, 0x2c, {'wfdno', 0x3d, r1}, 0x2c, {[{@cache_loose}, {@mmap}, {@loose}, {@loose}, {@mmap}], [{@mask={'mask', 0x3d, '^MAY_EXEC'}}, {@fsmagic={'fsmagic', 0x3d, 0x10001}}, {@dont_hash}]}}) Sample report: ================================================================== BUG: KASAN: use-after-free in kernfs_type include/linux/kernfs.h:335 [inline] BUG: KASAN: use-after-free in kernfs_leftmost_descendant fs/kernfs/dir.c:1261 [inline] BUG: KASAN: use-after-free in __kernfs_remove.part.0+0x843/0x960 fs/kernfs/dir.c:1369 Read of size 2 at addr ffff8880088807f0 by task syz-executor.2/857 CPU: 0 PID: 857 Comm: syz-executor.2 Not tainted 6.0.0-rc3-00363-g7726d4c3e60b #5 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x6e/0x91 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:317 [inline] print_report.cold+0x5e/0x5e5 mm/kasan/report.c:433 kasan_report+0xa3/0x130 mm/kasan/report.c:495 kernfs_type include/linux/kernfs.h:335 [inline] kernfs_leftmost_descendant fs/kernfs/dir.c:1261 [inline] __kernfs_remove.part.0+0x843/0x960 fs/kernfs/dir.c:1369 __kernfs_remove fs/kernfs/dir.c:1356 [inline] kernfs_remove_by_name_ns+0x108/0x190 fs/kernfs/dir.c:1589 sysfs_slab_add+0x133/0x1e0 mm/slub.c:5943 __kmem_cache_create+0x3e0/0x550 mm/slub.c:4899 create_cache mm/slab_common.c:229 [inline] kmem_cache_create_usercopy+0x167/0x2a0 mm/slab_common.c:335 p9_client_create+0xd4d/0x1190 net/9p/client.c:993 v9fs_session_init+0x1e6/0x13c0 fs/9p/v9fs.c:408 v9fs_mount+0xb9/0xbd0 fs/9p/vfs_super.c:126 legacy_get_tree+0xf1/0x200 fs/fs_context.c:610 vfs_get_tree+0x85/0x2e0 fs/super.c:1530 do_new_mount fs/namespace.c:3040 [inline] path_mount+0x675/0x1d00 fs/namespace.c:3370 do_mount fs/namespace.c:3383 [inline] __do_sys_mount fs/namespace.c:3591 [inline] __se_sys_mount fs/namespace.c:3568 [inline] __x64_sys_mount+0x282/0x300 fs/namespace.c:3568 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f725f983aed Code: 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f725f0f7028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f725faa3f80 RCX: 00007f725f983aed RDX: 00000000200000c0 RSI: 0000000020000040 RDI: 0000000000000000 RBP: 00007f725f9f419c R08: 0000000020000280 R09: 0000000000000000 R10: 0000000000000408 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000006 R14: 00007f725faa3f80 R15: 00007f725f0d7000 </TASK> Allocated by task 855: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:437 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:470 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:7 ---truncated---
The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2022-50432 since 09/17/2025. The exploitability is told to be easy. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 01/20/2026).
The vulnerability scanner Nessus provides a plugin with the ID 276806 (SUSE SLES15 Security Update : kernel (Live Patch 60 for SUSE Linux Enterprise 15 SP3) (SUSE-SU-2025:4172-1)), which helps to determine the existence of the flaw in a target environment.
Upgrading to version 4.9.332, 4.14.298, 4.19.264, 5.4.223, 5.10.153, 5.15.77 or 6.0.7 eliminates this vulnerability. Applying the patch 4dfd6a477a1525773469feaf3c514b2c0fef76b5/c78b0dc6fb7fb389d674e491fd376388cdfb1d53/6f72a3977ba9d0e5491a5c01315204272e7f9c44/94d2643df1e70a4c310ebb5e2c493eec33df1a06/af1b57cc39beca203559576b3046094fc9e5eb32/4abc99652812a2ddf932f137515d5c5a04723538 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.
The vulnerability is also documented in the databases at Tenable (276806) and CERT Bund (WID-SEC-2025-2187). Once again VulDB remains the best source for vulnerability data.
Affected
- Amazon Linux 2
- Red Hat Enterprise Linux
- SUSE Linux
- Oracle Linux
- Open Source Linux Kernel
- Dell Secure Connect Gateway
Product
Type
Vendor
Name
Version
- 4.9.331
- 4.14.297
- 4.19.263
- 5.4.222
- 5.10.152
- 5.15.0
- 5.15.1
- 5.15.2
- 5.15.3
- 5.15.4
- 5.15.5
- 5.15.6
- 5.15.7
- 5.15.8
- 5.15.9
- 5.15.10
- 5.15.11
- 5.15.12
- 5.15.13
- 5.15.14
- 5.15.15
- 5.15.16
- 5.15.17
- 5.15.18
- 5.15.19
- 5.15.20
- 5.15.21
- 5.15.22
- 5.15.23
- 5.15.24
- 5.15.25
- 5.15.26
- 5.15.27
- 5.15.28
- 5.15.29
- 5.15.30
- 5.15.31
- 5.15.32
- 5.15.33
- 5.15.34
- 5.15.35
- 5.15.36
- 5.15.37
- 5.15.38
- 5.15.39
- 5.15.40
- 5.15.41
- 5.15.42
- 5.15.43
- 5.15.44
- 5.15.45
- 5.15.46
- 5.15.47
- 5.15.48
- 5.15.49
- 5.15.50
- 5.15.51
- 5.15.52
- 5.15.53
- 5.15.54
- 5.15.55
- 5.15.56
- 5.15.57
- 5.15.58
- 5.15.59
- 5.15.60
- 5.15.61
- 5.15.62
- 5.15.63
- 5.15.64
- 5.15.65
- 5.15.66
- 5.15.67
- 5.15.68
- 5.15.69
- 5.15.70
- 5.15.71
- 5.15.72
- 5.15.73
- 5.15.74
- 5.15.75
- 5.15.76
- 6.0.0
- 6.0.1
- 6.0.2
- 6.0.3
- 6.0.4
- 6.0.5
- 6.0.6
License
Website
- Vendor: https://www.kernel.org/
CPE 2.3
CPE 2.2
CVSSv4
VulDB Vector: 🔒VulDB Reliability: 🔍
CVSSv3
VulDB Meta Base Score: 7.9VulDB Meta Temp Score: 7.7
VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔒
VulDB Reliability: 🔍
NVD Base Score: 7.8
NVD Vector: 🔒
CVSSv2
| AV | AC | Au | C | I | A |
|---|---|---|---|---|---|
| 💳 | 💳 | 💳 | 💳 | 💳 | 💳 |
| 💳 | 💳 | 💳 | 💳 | 💳 | 💳 |
| 💳 | 💳 | 💳 | 💳 | 💳 | 💳 |
| Vector | Complexity | Authentication | Confidentiality | Integrity | Availability |
|---|---|---|---|---|---|
| Unlock | Unlock | Unlock | Unlock | Unlock | Unlock |
| Unlock | Unlock | Unlock | Unlock | Unlock | Unlock |
| Unlock | Unlock | Unlock | Unlock | Unlock | Unlock |
VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍
Exploiting
Class: Use after freeCWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒
Physical: Partially
Local: Yes
Remote: Partially
Availability: 🔒
Status: Not defined
EPSS Score: 🔒
EPSS Percentile: 🔒
Price Prediction: 🔍
Current Price Estimation: 🔒
| 0-Day | Unlock | Unlock | Unlock | Unlock |
|---|---|---|---|---|
| Today | Unlock | Unlock | Unlock | Unlock |
Nessus ID: 276806
Nessus Name: SUSE SLES15 Security Update : kernel (Live Patch 60 for SUSE Linux Enterprise 15 SP3) (SUSE-SU-2025:4172-1)
Threat Intelligence
Interest: 🔍Active Actors: 🔍
Active APT Groups: 🔍
Countermeasures
Recommended: UpgradeStatus: 🔍
0-Day Time: 🔒
Upgrade: Kernel 4.9.332/4.14.298/4.19.264/5.4.223/5.10.153/5.15.77/6.0.7
Patch: 4dfd6a477a1525773469feaf3c514b2c0fef76b5/c78b0dc6fb7fb389d674e491fd376388cdfb1d53/6f72a3977ba9d0e5491a5c01315204272e7f9c44/94d2643df1e70a4c310ebb5e2c493eec33df1a06/af1b57cc39beca203559576b3046094fc9e5eb32/4abc99652812a2ddf932f137515d5c5a04723538
Timeline
09/17/2025 CVE reserved10/01/2025 Advisory disclosed
10/01/2025 VulDB entry created
01/20/2026 VulDB entry last update
Sources
Vendor: kernel.orgAdvisory: git.kernel.org
Status: Confirmed
CVE: CVE-2022-50432 (🔒)
GCVE (CVE): GCVE-0-2022-50432
GCVE (VulDB): GCVE-100-326532
CERT Bund: WID-SEC-2025-2187 - Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service
Entry
Created: 10/01/2025 14:41Updated: 01/20/2026 17:56
Changes: 10/01/2025 14:41 (58), 10/27/2025 03:08 (7), 11/19/2025 21:55 (2), 11/28/2025 18:39 (2), 01/20/2026 17:56 (12)
Complete: 🔍
Cache ID: 216::103
Once again VulDB remains the best source for vulnerability data.
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