CVE-2026-23554

Description

A flaw was found in Xen. An optimization in the Intel Extended Page Table (EPT) paging code, used by Xen, defers flushing cached EPT state. However, the freeing of paging structures is not similarly deferred. This can result in freed memory pages remaining in the cached state, allowing stale entries to point to memory regions not intended for guest access. A malicious guest could potentially exploit this to access unintended memory regions, leading to information disclosure or privilege escalation.

Statement

Red Hat Product Security has determined that this vulnerability does not affect any currently supported Red Hat product. This assessment may evolve based on further analysis and discovery. For more information about this vulnerability and the products it affects, please see the linked references.

Understanding the Weakness (CWE)

Confidentiality

Technical Impact: Read Memory

If the expired pointer is used in a read operation, an attacker might be able to control data read in by the application.

Availability

Technical Impact: DoS: Crash, Exit, or Restart

If the expired pointer references a memory location that is not accessible to the product, or points to a location that is "malformed" (such as NULL) or larger than expected by a read or write operation, then a crash may occur.

Integrity,Confidentiality,Availability

Technical Impact: Execute Unauthorized Code or Commands

If the expired pointer is used in a function call, or points to unexpected data in a write operation, then code execution may be possible.

Frequently Asked Questions

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