CVE-2020-29129

Description

An out-of-bounds access issue was found in the SLiRP user networking implementation of QEMU. It could occur while processing ARP/NCSI packets, if the packet length was shorter than required to accommodate respective protocol headers and payload. A privileged guest user may use this flaw to potentially leak host information bytes.

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 Score2.54.3N/A
Attack VectorLocalNetworkN/A
Attack ComplexityHighLowN/A
Privileges RequiredHighLowN/A
User InteractionNoneNoneN/A
ScopeChangedUnchangedN/A
ConfidentialityLowLowN/A
Integrity ImpactNoneNoneN/A
Availability ImpactNoneNoneN/A

Vector

Red Hat: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:L/I:N/A:N

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

Understanding the Weakness (CWE)

Confidentiality

Technical Impact: Read Memory

An attacker could get secret values such as cryptographic keys, PII, memory addresses, or other information that could be used in additional attacks.

Confidentiality

Technical Impact: Bypass Protection Mechanism

Out-of-bounds memory could contain memory addresses or other information that can be used to bypass ASLR and other protection mechanisms in order to improve the reliability of exploiting a separate weakness for code execution.

Availability

Technical Impact: DoS: Crash, Exit, or Restart

An attacker could cause a segmentation fault or crash by causing memory to be read outside of the bounds of the buffer. This is especially likely when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string.

Other

Technical Impact: Varies by Context

The read operation could produce other undefined or unexpected results.

Acknowledgements

Red Hat would like to thank Qiuhao Li for reporting this issue.

Frequently Asked Questions

Want to get errata notifications? Sign up here.