Linux Kernel up to 6.0.6 tipc_topsrv_stop null pointer dereference

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5.0	$0-$5k	0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Linux Kernel up to 4.19.263/5.4.222/5.10.152/5.15.76/6.0.6. This issue affects the function tipc_topsrv_stop. Executing a manipulation can lead to null pointer dereference. This vulnerability is handled as CVE-2022-50555. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 4.19.263/5.4.222/5.10.152/5.15.76/6.0.6 and classified as critical. This vulnerability affects the function tipc_topsrv_stop. The manipulation with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. As an impact it is known to affect availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: tipc: fix a null-ptr-deref in tipc_topsrv_accept syzbot found a crash in tipc_topsrv_accept: KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] Workqueue: tipc_rcv tipc_topsrv_accept RIP: 0010:kernel_accept+0x22d/0x350 net/socket.c:3487 Call Trace: <TASK> tipc_topsrv_accept+0x197/0x280 net/tipc/topsrv.c:460 process_one_work+0x991/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 It was caused by srv->listener that might be set to null by tipc_topsrv_stop() in net .exit whereas it's still used in tipc_topsrv_accept() worker. srv->listener is protected by srv->idr_lock in tipc_topsrv_stop(), so add a check for srv->listener under srv->idr_lock in tipc_topsrv_accept() to avoid the null-ptr-deref. To ensure the lsock is not released during the tipc_topsrv_accept(), move sock_release() after tipc_topsrv_work_stop() where it's waiting until the tipc_topsrv_accept worker to be done. Note that sk_callback_lock is used to protect sk->sk_user_data instead of srv->listener, and it should check srv in tipc_topsrv_listener_data_ready() instead. This also ensures that no more tipc_topsrv_accept worker will be started after tipc_conn_close() is called in tipc_topsrv_stop() where it sets sk->sk_user_data to null.

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2022-50555 since 10/07/2025. The exploitation appears to be difficult. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 284758 (EulerOS 2.0 SP10 : kernel (EulerOS-SA-2026-1029)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.19.264, 5.4.223, 5.10.153, 5.15.77 or 6.0.7 eliminates this vulnerability. Applying the patch ce69bdac2310152bb70845024d5d704c52aabfc3/24b129aed8730e48f47d852d58d76825ab6f407c/32a3d4660b34ce49ac0162338ebe362098e2f5df/7a939503fc32bff4ed60800b73ff7fbb4aea2142/cedb41664e27b2cae7e21487f1bee22dcd84037d/82cb4e4612c633a9ce320e1773114875604a3cce 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 (284758) and CERT Bund (WID-SEC-2025-2229). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• RESF Rocky Linux
• Open Source Linux Kernel
• IBM QRadar SIEM
• Dell NetWorker

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 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

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.1
VulDB Meta Temp Score: 5.0

VulDB Base Score: 4.8
VulDB Temp Score: 4.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔒

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 284758
Nessus Name: EulerOS 2.0 SP10 : kernel (EulerOS-SA-2026-1029)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 4.19.264/5.4.223/5.10.153/5.15.77/6.0.7
Patch: ce69bdac2310152bb70845024d5d704c52aabfc3/24b129aed8730e48f47d852d58d76825ab6f407c/32a3d4660b34ce49ac0162338ebe362098e2f5df/7a939503fc32bff4ed60800b73ff7fbb4aea2142/cedb41664e27b2cae7e21487f1bee22dcd84037d/82cb4e4612c633a9ce320e1773114875604a3cce

Timelineinfo

10/07/2025 Advisory disclosed
10/07/2025 +0 days CVE reserved
10/07/2025 +0 days VulDB entry created
04/20/2026 +195 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2022-50555 (🔒)
GCVE (CVE): GCVE-0-2022-50555
GCVE (VulDB): GCVE-100-327496
CERT Bund: WID-SEC-2025-2229 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 10/07/2025 19:27
Updated: 04/20/2026 02:11
Changes: 10/07/2025 19:27 (58), 11/22/2025 22:59 (7), 12/22/2025 06:46 (1), 01/16/2026 08:26 (2), 02/05/2026 19:47 (12), 03/01/2026 08:37 (1), 04/20/2026 02:11 (1)
Complete: 🔍
Cache ID: 216::103

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