NULL pointer dereference in QEMU
Key facts
- Attack vector
- Local
- Privileges required
- High
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-476.
Summary
A NULL pointer dereference flaw was found in the megasas-gen2 SCSI host bus adapter emulation of QEMU in versions before and including 6.0. This issue occurs in the megasas_command_cancelled() callback function while dropping a SCSI request. This flaw allows a privileged guest user to crash the QEMU process on the host, resulting in a denial of service. The highest threat from this vulnerability is to system availability.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | QEMU | All QEMU versions before and including 6.0 | — | No fix listed | CNA |
- QEMU Vendor— Affected All QEMU versions before and including 6.0 Fixed in — No fix listed CNA
CPE configurations NVD · 2
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:* | up to 6.0.0 | Vulnerable | QEMU |
| cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* | 33 | Vulnerable | Fedoraproject |
- cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:* Versions up to 6.0.0 Vulnerable ·QEMU
- cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* Versions 33 Vulnerable ·Fedoraproject
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
Not affected: 8 products
- Red Hat Enterprise Linux 5
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 8 Advanced Virtualization
- Red Hat Enterprise Linux 9
- Red Hat OpenStack Platform 10 (Newton)
- Red Hat OpenStack Platform 13 (Queens)
Timeline
- 2026-10-02 Threatist record created from CVE-2020-35503
- 2026-10-03 Alias added: GHSA-x852-p4x4-vcgf
References
Sources
- CVE-2020-35503 · CVE Program
- CVE-2020-35503 · NVD
- FIRST EPSS
- GHSA-x852-p4x4-vcgf · GitHub Advisory Database · CC BY 4.0
- CVE-2020-35503 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences