CVE intelligence

CVE-2026-98900

Vulnerability intelligence

Published Oct 23, 2026Sources checked Oct 23, 2026

N/ACVSS not listedScore unavailable

What this means

Review the available evidence

CVE-2026-98900. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Microsoft Security Response Center guidance

Vendor revision: Oct 24, 2026

Release Notes

CISA KEVNot listedBased on the latest collected catalog

EPSSUnavailableNo current score collected

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-98900?

In the Linux kernel, the following vulnerability has been resolved:

xen/gntalloc: validate grant count before allocation

gntalloc_ioctl_alloc() allocates the grant-id array before checking whether the requested count fits within the global grant limit. Counts above that limit cannot succeed, so reject them before the user-controlled allocation reaches kcalloc().

Use a subtraction-based check while holding gref_mutex so adding the requested count cannot wrap. Also cast the count before advancing the per-file index so the page-size multiplication is performed in 64-bit arithmetic.

Source: NVD