Linux Kernel L2TP net/l2tp/l2tp_core.c sk_user_data null pointer dereference

CVSS Meta Temp Score
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CTI Interest Score
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5.9$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in Linux Kernel. This issue affects the function sk_user_data of the file net/l2tp/l2tp_core.c of the component L2TP Handler. The manipulation results in null pointer dereference. This vulnerability is reported as CVE-2022-4129. The attack can be launched remotely. No exploit exists. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel (Operating System) (affected version not known). Affected is the function sk_user_data of the file net/l2tp/l2tp_core.c of the component L2TP Handler. The manipulation with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as 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. This is going to have an impact on availability. CVE summarizes:

A flaw was found in the Linux kernel's Layer 2 Tunneling Protocol (L2TP). A missing lock when clearing sk_user_data can lead to a race condition and NULL pointer dereference. A local user could use this flaw to potentially crash the system causing a denial of service.

The weakness was disclosed 11/29/2022. The advisory is available at lore.kernel.org. This vulnerability is traded as CVE-2022-4129 since 11/23/2022. Technical details are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 234965 (Amazon Linux 2 : kernel (ALASKERNEL-5.10-2025-089)), which helps to determine the existence of the flaw in a target environment.

Applying a patch is able to eliminate this problem. The bugfix is ready for download at lore.kernel.org.

The vulnerability is also documented in the vulnerability database at Tenable (234965). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.0
VulDB Meta Temp Score: 5.9

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

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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: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 234965
Nessus Name: Amazon Linux 2 : kernel (ALASKERNEL-5.10-2025-089)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: lore.kernel.org

Timelineinfo

11/23/2022 🔍
11/29/2022 +6 days 🔍
11/29/2022 +0 days 🔍
04/30/2025 +883 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: FEDORA-2022-24041b1667
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2022-4129 (🔍)
GCVE (CVE): GCVE-0-2022-4129
GCVE (VulDB): GCVE-100-214482

Entryinfo

Created: 11/29/2022 07:38
Updated: 04/30/2025 07:42
Changes: 11/29/2022 07:38 (43), 12/24/2022 07:33 (1), 12/24/2022 07:40 (11), 04/14/2025 22:23 (16), 04/30/2025 07:42 (2)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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