CVE-2026-98469
Description
A flaw was found in the Linux kernel's Kernel-based Virtual Machine (KVM) subsystem for ARM64 architectures. Improper handling of specific debug register accesses in 32-bit ARM (AArch32) mode causes the hypervisor to encounter an internal assertion failure. A user inside a guest virtual machine can exploit this vulnerability by accessing these registers, leading to immediate termination of the virtual machine and resulting in a Denial of Service (DoS).
Statement
This vulnerability is rated as Moderate severity because exploitation is restricted to authenticated users inside a virtualized environment and only causes termination of the caller's guest rather than impacting the host hypervisor. On Red Hat Enterprise Linux systems hosting virtual machines on 64-bit ARM hardware, this issue can only be triggered if a guest executes in 32-bit compatibility mode and interacts with specific debug registers. The host system's availability, data integrity, and confidentiality remain protected, preventing broader multi-tenant compromise.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.5 | N/A | 7.1 |
| Attack Vector | Local | N/A | Local |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | Low | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Changed |
| Confidentiality | None | N/A | None |
| Integrity Impact | None | N/A | None |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
cve.org: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Crash, Exit, or Restart
While assertion is good for catching logic errors and reducing the chances of reaching more serious vulnerability conditions, an attacker can still cause a denial of service if they can trigger an assert statement, and if the scope of the assert() extends beyond the attacker's own session. For example, if a server handles multiple simultaneous connections, if an assert() occurs in one single connection that causes all other connections to be dropped, this could be a significant denial of service.
Frequently Asked Questions
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