CVE-2026-3842

A flaw was found in QEMU. This vulnerability allows a local attacker within a guest virtual machine to write data beyond its allocated memory. This occurs when cpu_physical_memory_map() returns a shorter length than expected, leading to an out-of-bounds write. Successful exploitation could result in unauthorized access to guest memory or corruption of heap-allocated objects, potentially causing information disclosure, data integrity issues, or a denial of service.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-3842
https://bugzilla.redhat.com/show_bug.cgi?id=2458150
https://access.redhat.com/security/cve/CVE-2026-3842
https://bugzilla.redhat.com/show_bug.cgi?id=2458150
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-3842.json

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-16 01:16

Updated : 2026-09-01 13:19

NVD link : CVE-2026-3842

Mitre link : CVE-2026-3842

CVE.ORG link : CVE-2026-3842

JSON object : View

Products Affected

No product.

CWE

CWE-787

Out-of-bounds Write

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