CVE-2018-17958

Description

An integer overflow issue was found in the RTL8139 NIC emulation in QEMU. It could occur while receiving packets over the network if the size value is greater than INT_MAX. Such overflow would lead to stack buffer overflow issue. A user inside guest could use this flaw to crash the QEMU process, resulting in DoS scenario.

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 Score6.57.57.5
Attack VectorNetworkNetworkNetwork
Attack ComplexityHighLowLow
Privileges RequiredNoneNoneNone
User InteractionNoneNoneNone
ScopeUnchangedUnchangedUnchanged
ConfidentialityNoneNoneNone
Integrity ImpactLowNoneNone
Availability ImpactHighHighHigh

Vector

Red Hat: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H

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

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

Understanding the Weakness (CWE)

Availability

Technical Impact: Modify Memory; DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory)

Buffer overflows generally lead to crashes. Other attacks leading to lack of availability are possible, including putting the program into an infinite loop.

Integrity,Confidentiality,Availability,Access Control

Technical Impact: Modify Memory; Execute Unauthorized Code or Commands; Bypass Protection Mechanism

Buffer overflows often can be used to execute arbitrary code, which is usually outside the scope of a program's implicit security policy.

Integrity,Confidentiality,Availability,Access Control,Other

Technical Impact: Modify Memory; Execute Unauthorized Code or Commands; Bypass Protection Mechanism; Other

When the consequence is arbitrary code execution, this can often be used to subvert any other security service.

Acknowledgements

Red Hat would like to thank Arash Tohidi and Daniel Shapira (Twistlock) for reporting this issue.

Frequently Asked Questions

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