Linux Kernel up to 6.12.109/6.18.51/7.2.5 arm_scmi mailbox_chan_setup denial of service

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.
5.3	$0-$5k	0.39-

Summaryinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.12.109/6.18.51/7.2.5. This affects the function mailbox_chan_setup of the component arm_scmi. The manipulation leads to denial of service. This vulnerability is traded as CVE-2026-93083. An attack has to be approached locally. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 6.12.109/6.18.51/7.2.5. This issue affects the function mailbox_chan_setup of the component arm_scmi. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: firmware: arm_scmi: Unwind TX receiver mailbox setup failure mailbox_chan_setup() can request an additional unidirectional TX receiver channel after successfully acquiring the primary channel. If that second request fails, the function returns immediately and leaves the primary channel allocated. Unwind the primary mailbox channel before returning the error so probe deferral or other setup failures do not leave the channel busy for later probe attempts.

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2026-93083 since 09/17/2026. The exploitation is known to be easy. An attack has to be approached locally. Technical details are known, but no exploit is available.

Upgrading to version 6.12.110, 6.18.52, 7.2.6 or 7.3-rc1 eliminates this vulnerability. Applying the patch babb017cf5e4600c94c23ea87175a0380235a3ee/717b8e972a667fc1bebe63cbcf0d58e692cbb491/9958f55eace8b43713c9fc54dcf90e7cdefee413/6f7c06744d53dc8e047725d411d7f915d9ec35ae is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.12.109
• 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
• 6.18.50
• 6.18.51
• 7.2.0
• 7.2.1
• 7.2.2
• 7.2.3
• 7.2.4
• 7.2.5

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: 5.5
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
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: Denial of service
CWE: CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

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 6.12.110/6.18.52/7.2.6/7.3-rc1
Patch: babb017cf5e4600c94c23ea87175a0380235a3ee/717b8e972a667fc1bebe63cbcf0d58e692cbb491/9958f55eace8b43713c9fc54dcf90e7cdefee413/6f7c06744d53dc8e047725d411d7f915d9ec35ae

Timelineinfo

09/17/2026 Advisory disclosed
09/17/2026 +0 days CVE reserved
09/17/2026 +0 days VulDB entry created
09/17/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-93083 (🔒)
GCVE (CVE): GCVE-0-2026-93083
GCVE (VulDB): GCVE-100-407189

Entryinfo

Created: 09/17/2026 23:41
Changes: 09/17/2026 23:41 (59)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Discussion

Do you need the next level of professionalism?

Upgrade your account now!