Linux Kernel up to 6.18.49/7.2.3 uverbs privileges management

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.2	$0-$5k	0.00+

Summaryinfo

A vulnerability categorized as critical has been discovered in Linux Kernel up to 6.18.49/7.2.3. The impacted element is an unknown function of the component uverbs. The manipulation results in privileges management. This vulnerability is identified as CVE-2026-89506. The attack can be executed remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.18.49/7.2.3. Affected is an unknown functionality of the component uverbs. The manipulation with an unknown input leads to a privileges management vulnerability. CWE is classifying the issue as CWE-269. The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor. This is going to have an impact on availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: RDMA/uverbs: Add UVERBS_ATTR_UHW to UVERBS_METHOD_REG_MR The original commit missed that three drivers (mthca, irdma, siw) have UHW data associated with reg_mr that cannot be passed through the ioctl. They also assume that the udata cannot be NULL, so failing to pass a valid udata can trigger a NULL udata crash in those drivers. This never happens in real systems since in rdma-core ibv_cmd_reg_mr_ex() does not accept a udata and those three drivers don't use it, however a malicious userspace could trigger it.

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2026-89506 since 09/11/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 09/12/2026). The MITRE ATT&CK project declares the attack technique as T1068.

Upgrading to version 6.18.50, 7.2.4 or 7.3-rc1 eliminates this vulnerability. Applying the patch 71d5c41ac583df09a7c32199bef7d42de7267d07/9e71d0f4944ba5641e01db29b3256c963656d671/011199f46f44a9fd93a9e5ab5d7fd1328d80e9bf is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.18.0
• 6.18.1
• 6.18.2
• 6.18.3
• 6.18.4
• 6.18.5
• 6.18.6
• 6.18.7
• 6.18.8
• 6.18.9
• 6.18.10
• 6.18.11
• 6.18.12
• 6.18.13
• 6.18.14
• 6.18.15
• 6.18.16
• 6.18.17
• 6.18.18
• 6.18.19
• 6.18.20
• 6.18.21
• 6.18.22
• 6.18.23
• 6.18.24
• 6.18.25
• 6.18.26
• 6.18.27
• 6.18.28
• 6.18.29
• 6.18.30
• 6.18.31
• 6.18.32
• 6.18.33
• 6.18.34
• 6.18.35
• 6.18.36
• 6.18.37
• 6.18.38
• 6.18.39
• 6.18.40
• 6.18.41
• 6.18.42
• 6.18.43
• 6.18.44
• 6.18.45
• 6.18.46
• 6.18.47
• 6.18.48
• 6.18.49
• 7.2.0
• 7.2.1
• 7.2.2
• 7.2.3

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.5
VulDB Meta Temp Score: 6.2

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

CVSSv2info

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: 🔍

Exploitinginfo

Class: Privileges management
CWE: CWE-269 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.18.50/7.2.4/7.3-rc1
Patch: 71d5c41ac583df09a7c32199bef7d42de7267d07/9e71d0f4944ba5641e01db29b3256c963656d671/011199f46f44a9fd93a9e5ab5d7fd1328d80e9bf

Timelineinfo

09/11/2026 CVE reserved
09/11/2026 +0 days VulDB entry created
09/12/2026 +0 days Advisory disclosed
09/12/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-89506 (🔒)
GCVE (CVE): GCVE-0-2026-89506
GCVE (VulDB): GCVE-100-402816

Entryinfo

Created: 09/12/2026 00:51
Changes: 09/12/2026 00:51 (58)
Complete: 🔍
Cache ID: 216::103

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Discussion

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