CVE-2026-80554

In the Linux kernel, the following vulnerability has been resolved: s390/vfio_ccw: Limit the number of channel program segments The processing of channel programs, and the CCWs within them, is done recursively. As such, there is an arbitrary (but not architectural) limit to the number of CCWs that can exist in a single channel program. The vfio-ccw logic breaks these channel programs into segments whenever it encounters a Transfer-In-Channel (TIC) CCW, and the combined number of segments count towards the global limit. Impose an equivalent limit to the number of segments until such logic can be made non-recursive.

CVSS v3 9.3 CRITICAL

9.3^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 2.5 / Impact : 6.0

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://git.kernel.org/stable/c/06f4d6e5a8af6c2072e8cd39dbc512c683ca7fb2
https://git.kernel.org/stable/c/15fb4559a7fdf0b8725e433a71cfd03a1313a48b
https://git.kernel.org/stable/c/4ee94790490ae8dcc97df8597f07836c8a81bbcf
https://git.kernel.org/stable/c/5405c90d6a47b3014e74ee0618a162449abbbc93
https://git.kernel.org/stable/c/a1625f66eaa1200068a0e2c05bc90e65182fc4e3

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-26 15:17

Updated : 2026-08-27 06:17

NVD link : CVE-2026-80554

Mitre link : CVE-2026-80554

CVE.ORG link : CVE-2026-80554

JSON object : View

Products Affected

No product.

CWE

No CWE.

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