Linux Kernel up to 6.6.152/6.12.104/6.18.45/7.1.9 s390-vfio_ccw vfio_ccw.c cp_free race condition

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.5$0-$5k0.92-

Summaryinfo

A vulnerability, which was classified as very critical, was found in Linux Kernel up to 6.6.152/6.12.104/6.18.45/7.1.9. This vulnerability affects the function cp_free of the file drivers/s390/vfio_ccw/vfio_ccw.c of the component s390-vfio_ccw. The manipulation results in race condition. This vulnerability was named CVE-2026-80548. The attack may be performed from remote. There is no available exploit.

Detailsinfo

A vulnerability classified as very critical has been found in Linux Kernel up to 6.6.152/6.12.104/6.18.45/7.1.9. Affected is the function cp_free of the file drivers/s390/vfio_ccw/vfio_ccw.c of the component s390-vfio_ccw. The manipulation with an unknown input leads to a race condition vulnerability. CWE is classifying the issue as CWE-362. The product contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: s390/vfio_ccw: Selectively expand io_mutex The io_mutex was defined to serialize the io_regions, but then has also sort of been associated with the I/O themselves because of the close relationship they share. With the handful of races that are possible, the choices are either to: A) expand the scope of io_mutex to close these remaining windows, or B) reduce the scope of io_mutex to just io_region, and introduce a new lock mechanism for the remaining I/O resources This patch implements A, since B brings with it a lot more interactions that would need to be tracked and kept in a correct hierarchy. It also takes advantage of the workqueue element for cp_free() that now gets called out of fsm_notoper(), which could be invoked out of an interrupt context and thus cannot acquire a mutex itself.

The advisory is available at git.kernel.org. This vulnerability is traded as CVE-2026-80548 since 08/26/2026. 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 $0-$5k at the moment (estimation calculated on 08/26/2026).

Upgrading to version 6.6.153, 6.12.105, 6.18.46 or 7.1.10 eliminates this vulnerability. Applying the patch f72a51810d49411bd8cad0c2df8592320a2fe5cc/2ba9efdf9ebedc4e54df4b56aa3b43a65f7967cd/b6aecea4b2b246f9fbd98a5712daa1193a60818e/2a5ac0c0f1f7da33929211a2e41911bf72ee35d8/34f4feff3e90bd09308fad0974e97113b23b812a is able to eliminate this problem.

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Productinfo

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Version

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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

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Race condition
CWE: CWE-362
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

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

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.6.153/6.12.105/6.18.46/7.1.10
Patch: f72a51810d49411bd8cad0c2df8592320a2fe5cc/2ba9efdf9ebedc4e54df4b56aa3b43a65f7967cd/b6aecea4b2b246f9fbd98a5712daa1193a60818e/2a5ac0c0f1f7da33929211a2e41911bf72ee35d8/34f4feff3e90bd09308fad0974e97113b23b812a

Timelineinfo

08/26/2026 Advisory disclosed
08/26/2026 +0 days CVE reserved
08/26/2026 +0 days VulDB entry created
08/26/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-80548 (🔒)
GCVE (CVE): GCVE-0-2026-80548
GCVE (VulDB): GCVE-100-395838

Entryinfo

Created: 08/26/2026 17:32
Changes: 08/26/2026 17:32 (60)
Complete: 🔍
Cache ID: 216::103

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