Security readout for executives and security teams
Plain-English summary
A malformed VMDK virtual-disk image can make QEMU read beyond an allocated heap buffer. The stated consequences are a small, 12-byte information leak or a QEMU denial of service. This is a moderate operational risk, especially where users or automation can introduce untrusted disk images.
Executive priority
Prioritize near-term inventory and exposure reduction rather than emergency response. Accelerate remediation for shared virtualization or image-import services accepting externally supplied VMDKs. Systems processing only controlled images have lower practical exposure, but affected package status should still be tracked.
Technical view
CVE-2026-2243 is a CWE-125 out-of-bounds read in QEMU's compressed VMDK grain parsing. It has CVSS 3.1 score 5.1: local, low-complexity, no privileges or user interaction, with low confidentiality and availability impact. Integrity impact is not identified.
Likely exposure
Exposure is most likely where affected QEMU or qemu-kvm deployments process untrusted VMDK images. The bundle marks RHEL 8, 9, and 10 and OpenShift 4 packages as affected. RHEL 6 and 7 status is unknown; the generic qemu entry is marked unaffected.
Exploitation context
The CVSS vector identifies a local attack path. Triggering requires QEMU to parse a specially crafted VMDK image. The supplied record is not in KEV, and the cited material provides no evidence of active exploitation or public weaponization.
Researcher notes
The documented impact is narrowly bounded to a possible 12-byte disclosure or denial of service; code execution and integrity compromise are not claimed. Exact affected versions, patched versions, and technical parsing details are absent from the bundle. RHEL 6 and 7 require vendor confirmation because their status is unknown.
Mitigation direction
- Identify affected qemu-kvm packages and systems that import, convert, attach, or inspect VMDK images.
- Prevent untrusted VMDK images from reaching affected QEMU workflows until remediation is confirmed.
- Restrict image-upload and virtualization-management access to trusted users and services.
- Check Red Hat guidance for applicable updates or mitigations; none are named in the supplied bundle.
Validation and detection
- Compare installed qemu-kvm packages with Red Hat's current CVE status for each operating system.
- Map every workflow that accepts VMDK images, including uploads, migrations, conversions, and automated imports.
- Confirm untrusted users cannot submit VMDK images to affected hosts or OpenShift virtualization workflows.
- Review QEMU failures associated with VMDK processing, without treating crashes alone as proof of exploitation.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-125: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupContainer behavior lookup
The affected technology mentions containers, so container-specific ATT&CK technique review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-2243 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L2.52.5redhatVulnerability scoring details
Base CVSS 3.1 score
5.1MediumVector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- Source timelineredhat
Made public.
- Source timelineredhat
Reported to Red Hat.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://access.redhat.com/security/cve/CVE-2026-2243CVE reference, redhat · vdb-entry, x_refsource_REDHAT
- RHBZ#2440934CVE reference, redhat · issue-tracking, x_refsource_REDHAT
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Out-of-bounds Read
Out-of-bounds Read represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.