QEMU KVM hw/hyperv/syndbg.c cpu_physical_memory_map out-of-bounds write

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability labeled as critical has been found in QEMU. Affected by this issue is the function cpu_physical_memory_map of the file hw/hyperv/syndbg.c of the component KVM. Executing a manipulation can lead to out-of-bounds write. This vulnerability appears as CVE-2026-3842. The physical device can be targeted for the attack. There is no available exploit. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability was found in QEMU (the affected version unknown). It has been declared as critical. This vulnerability affects the function cpu_physical_memory_map of the file hw/hyperv/syndbg.c of the component KVM. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. The CWE definition for the vulnerability is CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability.

The advisory is available at bugzilla.redhat.com. This vulnerability was named CVE-2026-3842. The exploitation appears to be easy. Local access is required to approach this attack. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 07/16/2026).

The vulnerability scanner Nessus provides a plugin with the ID 310544 (Oracle Linux 8 : virt:kvm_utils3 (ELSA-2026-50239)), which helps to determine the existence of the flaw in a target environment.

Applying the patch 4f28b87fdd24df2049626106b7c24d0180952115 is able to eliminate this problem. The bugfix is ready for download at gitlab.com.

The vulnerability is also documented in the databases at Tenable (310544) and EUVD (EUVD-2026-44840). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.6
VulDB Meta Temp Score: 6.3

VulDB Base Score: 6.6
VulDB Temp Score: 6.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Yes
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 310544
Nessus Name: Oracle Linux 8 : virt:kvm_utils3 (ELSA-2026-50239)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: 4f28b87fdd24df2049626106b7c24d0180952115

Timelineinfo

04/17/2026 Advisory disclosed
04/17/2026 +0 days VulDB entry created
07/16/2026 +90 days VulDB entry last update

Sourcesinfo

Product: qemu.org

Advisory: bugzilla.redhat.com
Status: Confirmed

CVE: CVE-2026-3842 (🔒)
GCVE (CVE): GCVE-0-2026-3842
GCVE (VulDB): GCVE-100-358018
EUVD: 🔒

Entryinfo

Created: 04/17/2026 06:54
Updated: 07/16/2026 04:46
Changes: 04/17/2026 06:54 (54), 04/28/2026 06:08 (2), 07/16/2026 04:46 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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