CVE-2026-24708

Description

A flaw in OpenStack Nova’s interaction with the qemu-img utility allows an authenticated user to overwrite arbitrary files on the compute host. This occurs because Nova invokes qemu-img without strictly constraining the disk image format, enabling a malicious user to craft a QCOW2 header on a raw disk and trigger destructive behavior during instance operations such as resize.

Statement

This vulnerability is rated Important for Red Hat OpenStack Platform. An authenticated attacker can exploit unconstrained disk format handling in OpenStack Nova when invoking qemu-img. By crafting a QCOW2 header on an ephemeral or root disk, an attacker can cause qemu-img to overwrite arbitrary files on the compute host with Nova's write access, leading to data destruction or denial of service.

Mitigation

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

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).

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score7.1N/A7.1
Attack VectorLocalN/ALocal
Attack ComplexityLowN/ALow
Privileges RequiredLowN/ALow
User InteractionNoneN/ANone
ScopeUnchangedN/AUnchanged
ConfidentialityNoneN/ANone
Integrity ImpactHighN/AHigh
Availability ImpactHighN/AHigh

Vector

Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H

cve.org: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H

Understanding the Weakness (CWE)

Integrity,Confidentiality

Technical Impact: Read Files or Directories; Modify Files or Directories

The application can operate on unexpected files. Confidentiality is violated when the targeted filename is not directly readable by the attacker.

Integrity,Confidentiality,Availability

Technical Impact: Modify Files or Directories; Execute Unauthorized Code or Commands

The application can operate on unexpected files. This may violate integrity if the filename is written to, or if the filename is for a program or other form of executable code.

Availability

Technical Impact: DoS: Crash, Exit, or Restart; DoS: Resource Consumption (Other)

The application can operate on unexpected files. Availability can be violated if the attacker specifies an unexpected file that the application modifies. Availability can also be affected if the attacker specifies a filename for a large file, or points to a special device or a file that does not have the format that the application expects.

Acknowledgements

Red Hat would like to thank Dan Smith (RedHat) for reporting this issue.

Frequently Asked Questions

Want to get errata notifications? Sign up here.