Linux Kernel up to 6.12.104/6.18.45/7.1.9 s390-vfio_ccw ccwchain_handle_ccw allocation of resources

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-$5k0.00-

Summaryinfo

A vulnerability classified as very critical was found in Linux Kernel up to 6.12.104/6.18.45/7.1.9. The impacted element is the function ccwchain_handle_ccw of the component s390-vfio_ccw. Such manipulation leads to allocation of resources. This vulnerability is traded as CVE-2026-80555. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.12.104/6.18.45/7.1.9. It has been rated as very critical. Affected by this issue is the function ccwchain_handle_ccw of the component s390-vfio_ccw. The manipulation with an unknown input leads to a allocation of resources vulnerability. Using CWE to declare the problem leads to CWE-770. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor. Impacted is confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: s390/vfio_ccw: Free all memory if cp_init() fails The routine cp_free() is called to unpin/free any memory once an I/O is completed successfully, or if cp_prefetch() fails. But if cp_init() fails, and cp->initialized is not enabled, the same routine cannot be used to free all the memory. An attempt to address this exists in ccwchain_handle_ccw(), where a single call to ccwchain_free() is made for the currently-processed CCW segment. But this will leak other segments (created as a result of a Transfer in Channel) that had been allocated as part of the same channel program. Address this by performing the cleanup outside of the recursive ccwchain_handle_ccw()/ccwchain_loop_tic() logic.

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2026-80555 since 08/26/2026. The exploitation is known to be easy. The attack may be launched remotely. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 08/26/2026). The MITRE ATT&CK project declares the attack technique as T1499.

Upgrading to version 6.12.105, 6.18.46 or 7.1.10 eliminates this vulnerability. Applying the patch 6a917199aaf97904f5619afe3dfdacb155b03e8c/32e3d364a7b8295120d37e6a6bd433d2de26f748/4699b54fada156534cbb39834d47fc9374d7a1f5/74186c2968f8f756ac3226b545b598457c910c75 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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💳💳💳💳💳💳
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Allocation of resources
CWE: CWE-770 / CWE-400 / CWE-404
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 6.12.105/6.18.46/7.1.10
Patch: 6a917199aaf97904f5619afe3dfdacb155b03e8c/32e3d364a7b8295120d37e6a6bd433d2de26f748/4699b54fada156534cbb39834d47fc9374d7a1f5/74186c2968f8f756ac3226b545b598457c910c75

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-2026-80555 (🔒)
GCVE (CVE): GCVE-0-2026-80555
GCVE (VulDB): GCVE-100-395864

Entryinfo

Created: 08/26/2026 17:51
Changes: 08/26/2026 17:51 (59)
Complete: 🔍
Cache ID: 216::103

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