Linux Kernel up to 6.0.2 set_pub_key null pointer dereference

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5.5	$0-$5k	0.00

Summaryinfo

A vulnerability described as critical has been identified in Linux Kernel up to 5.4.219/5.10.149/5.15.74/5.19.16/6.0.2. The impacted element is the function set_pub_key. Such manipulation leads to null pointer dereference. This vulnerability is documented as CVE-2022-50731. There is not any exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 5.4.219/5.10.149/5.15.74/5.19.16/6.0.2. Affected by this issue is the function set_pub_key. The manipulation with an unknown input leads to a null pointer dereference vulnerability. Using CWE to declare the problem leads to 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. Impacted is availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: crypto: akcipher - default implementation for setting a private key Changes from v1: * removed the default implementation from set_pub_key: it is assumed that an implementation must always have this callback defined as there are no use case for an algorithm, which doesn't need a public key Many akcipher implementations (like ECDSA) support only signature verifications, so they don't have all callbacks defined. Commit 78a0324f4a53 ("crypto: akcipher - default implementations for request callbacks") introduced default callbacks for sign/verify operations, which just return an error code. However, these are not enough, because before calling sign the caller would likely call set_priv_key first on the instantiated transform (as the in-kernel testmgr does). This function does not have a default stub, so the kernel crashes, when trying to set a private key on an akcipher, which doesn't support signature generation. I've noticed this, when trying to add a KAT vector for ECDSA signature to the testmgr. With this patch the testmgr returns an error in dmesg (as it should) instead of crashing the kernel NULL ptr dereference.

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2022-50731 since 12/24/2025. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 279939 (Linux Distros Unpatched Vulnerability : CVE-2022-50731), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.4.220, 5.10.150, 5.15.75, 5.19.17 or 6.0.3 eliminates this vulnerability. Applying the patch 95c4e20adc3ea00d1594a2a05d9b187ed12ffa8e/a1354bdd191d533211b7cb723aa76a66f516f197/779a9930f3e152c82699feb389a0e6d6644e747e/85bc736a18b872f54912e8bb70682d11770aece0/f9058178597059d6307efe96a7916600f8ede08c/bc155c6c188c2f0c5749993b1405673d25a80389 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 (279939) and CERT Bund (WID-SEC-2025-2929). Once again VulDB remains the best source for vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• Open Source Linux Kernel

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.4.219
• 5.10.149
• 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
• 5.19.0
• 5.19.1
• 5.19.2
• 5.19.3
• 5.19.4
• 5.19.5
• 5.19.6
• 5.19.7
• 5.19.8
• 5.19.9
• 5.19.10
• 5.19.11
• 5.19.12
• 5.19.13
• 5.19.14
• 5.19.15
• 5.19.16
• 6.0.0
• 6.0.1
• 6.0.2

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: 5.7
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.7
VulDB Temp Score: 5.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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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: No
Local: No
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: 279939
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2022-50731

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.4.220/5.10.150/5.15.75/5.19.17/6.0.3
Patch: 95c4e20adc3ea00d1594a2a05d9b187ed12ffa8e/a1354bdd191d533211b7cb723aa76a66f516f197/779a9930f3e152c82699feb389a0e6d6644e747e/85bc736a18b872f54912e8bb70682d11770aece0/f9058178597059d6307efe96a7916600f8ede08c/bc155c6c188c2f0c5749993b1405673d25a80389

Timelineinfo

12/24/2025 Advisory disclosed
12/24/2025 +0 days CVE reserved
12/24/2025 +0 days VulDB entry created
04/21/2026 +118 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2022-50731 (🔒)
GCVE (CVE): GCVE-0-2022-50731
GCVE (VulDB): GCVE-100-337916
CERT Bund: WID-SEC-2025-2929 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 12/24/2025 14:07
Updated: 04/21/2026 02:35
Changes: 12/24/2025 14:07 (58), 12/26/2025 08:40 (2), 12/29/2025 16:16 (7), 04/21/2026 02:35 (1)
Complete: 🔍
Cache ID: 216::103

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