CVE-2018-16866

Description

An out of bounds read was discovered in systemd-journald in the way it parses log messages that terminate with a colon ':'. A local attacker can use this flaw to disclose process memory data.

Statement

This issue affects the versions of systemd as shipped with Red Hat Enterprise Linux 7. Red Hat Product Security has rated this issue as having a security impact of Moderate. For additional information, refer to the Issue Severity Classification: https://access.redhat.com/security/updates/classification/.

Red Hat Virtualization Hypervisor and Management Appliance include vulnerable versions of systemd. However, since exploitation requires local access and impact is restricted to information disclosure, this flaw is rated as having a security issue of Low. Future updates may address this issue.

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 Score4.33.3N/A
Attack VectorAdjacent NetworkLocalN/A
Attack ComplexityLowLowN/A
Privileges RequiredNoneLowN/A
User InteractionNoneNoneN/A
ScopeUnchangedUnchangedN/A
ConfidentialityLowLowN/A
Integrity ImpactNoneNoneN/A
Availability ImpactNoneNoneN/A

Vector

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

NVD: CVSS:3.1/AV:L/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 Qualys Research Labs for reporting this issue.

Frequently Asked Questions

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