Linux Kernel up to 6.6.156/6.12.109/6.18.51/7.2.5 dw-edma client.rst vchan_cookie_complete use after free

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.
9.5	$5k-$25k	0.00+

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.6.156/6.12.109/6.18.51/7.2.5 and classified as very critical. Impacted is the function vchan_cookie_complete of the file Documentation/driver-api/dmaengine/client.rst of the component dw-edma. The manipulation results in use after free. This vulnerability is reported as CVE-2026-93042. The attack can be launched remotely. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as very critical, was found in Linux Kernel up to 6.6.156/6.12.109/6.18.51/7.2.5. Affected is the function vchan_cookie_complete of the file Documentation/driver-api/dmaengine/client.rst of the component dw-edma. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: dmaengine: dw-edma: Terminate all descriptors without callbacks The DMA Engine client documentation says in the "Terminate APIs" section of Documentation/driver-api/dmaengine/client.rst: "No callback functions will be called for any incomplete transfers." dw-edma instead calls vchan_cookie_complete() when a deferred STOP reaches the interrupt handler. This schedules a callback for the active descriptor and leaves other issued or submitted descriptors queued. A late callback after dmaengine_terminate_sync() can dereference client state that has already been freed, while leftover descriptors may later restart into reused buffers or leak. Move all issued and submitted descriptors to the terminated list whenever termination completes. For a pending STOP, do this from both the DONE and ABORT paths. Complete their cookies in order without scheduling callbacks. A STOP can remain pending until the running transfer raises an interrupt. Make device_synchronize() wait for such a pending STOP to complete before releasing terminated descriptors. Reuse it from free_chan_resources(), then release the remaining virt-dma resources. Sleep instead of busy-polling while waiting, and warn if the existing timeout expires.

The advisory is available at git.kernel.org. This vulnerability is traded as CVE-2026-93042 since 09/17/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 09/17/2026).

Upgrading to version 6.6.157, 6.12.110, 6.18.52, 7.2.6 or 7.3-rc1 eliminates this vulnerability. Applying the patch 65e387b95d3855aa894ac729e1778e5bcb9083cb/4793f9099a1cadf4e37f3a03d524af6bce88a0ea/be87d86537de7ea6fd025f41033d2faff880973f/f3ec6702a1d216be61f692cc0a983d6c8fb5ebf7/99109a51efd28c9a661fbfb9469b023c517b31d1 is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

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

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.6.156
• 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: 9.9
VulDB Meta Temp Score: 9.5

VulDB Base Score: 9.9
VulDB Temp Score: 9.5
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: Use after free
CWE: CWE-416 / CWE-119
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 6.6.157/6.12.110/6.18.52/7.2.6/7.3-rc1
Patch: 65e387b95d3855aa894ac729e1778e5bcb9083cb/4793f9099a1cadf4e37f3a03d524af6bce88a0ea/be87d86537de7ea6fd025f41033d2faff880973f/f3ec6702a1d216be61f692cc0a983d6c8fb5ebf7/99109a51efd28c9a661fbfb9469b023c517b31d1

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-2026-93042 (🔒)
GCVE (CVE): GCVE-0-2026-93042
GCVE (VulDB): GCVE-100-407082

Entryinfo

Created: 09/17/2026 23:01
Changes: 09/17/2026 23:01 (60)
Complete: 🔍
Cache ID: 216::103

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

Discussion

Do you need the next level of professionalism?

Upgrade your account now!