CVE-2026-89593

In the Linux kernel, the following vulnerability has been resolved: hugetlb: only adjust reservation during unmapping if mapcount is 0 Since df7a6d1f6405, __unmap_hugepage_range can adjust reservations. In the case of folio mapped in both a parent and a child, if the parent unmaps the range first, the reservation adjustment will result in an underflow of the reserved count. Once the child unmaps the range, the count is restored. Change __unmap_hugepage_range() to check the mapcount before adjusting the reservation.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/0f001491e5a2ec69aa9d5dd6b799e5742245f9ea
https://git.kernel.org/stable/c/5120b1e048d48596ffaec1a8412012a91adba73b
https://git.kernel.org/stable/c/a3c65af20cceb7f997847727636b4017326f845d
https://git.kernel.org/stable/c/b0b1b9ca80b795ed2223e76dd787db7067121fb9

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-11 20:19

Updated : 2026-09-14 13:19

NVD link : CVE-2026-89593

Mitre link : CVE-2026-89593

CVE.ORG link : CVE-2026-89593

JSON object : View

Products Affected

No product.

CWE

No CWE.

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