Vulnerability in Linux

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.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H.

EPSS exploit prediction

EPSS: 0.001 (2.2th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 2nd percentile — 2.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-89593: held from 0.002 to 0.001.

EPSS over last 30 days · oldest: 0.002 · newest: 0.001 · change: -0.000

Affected products

References

Frequently asked questions

What is CVE-2026-89593?
CVE-2026-89593 is a high-severity vulnerability in Linux. CVSS score: 7.1/10. Published 2026-09-11.
How severe is CVE-2026-89593?
High severity. CVSS v3 base score is 7.1 out of 10.