CoreCVE
Back

HIGH

ruby: Buffer under-read in String#unpack

Published Apr 3, 2018

Description

In Ruby before 2.2.10, 2.3.x before 2.3.7, 2.4.x before 2.4.4, 2.5.x before 2.5.1, and 2.6.0-preview1, an attacker controlling the unpacking format (similar to format string vulnerabilities) can trigger a buffer under-read in the String#unpack method, resulting in a massive and controlled information disclosure.

Affected products

Remediation

Red Hat statement

This issue affects the versions of ruby as shipped with Red Hat CloudForms 4. Red Hat Product Security has rated this issue as having security impact of Moderate. A future update may address this issue. For additional information, refer to the Issue Severity Classification: https://access.redhat.com/security/updates/classification/. This issue affects the versions of ruby as shipped with Red Hat Subscription Asset Manager 1. Red Hat Product Security has rated this issue as having security impact of Moderate. A future update may address this issue. For additional information, refer to the Issue Severity Classification: https://access.redhat.com/security/updates/classification/.

Red Hat mitigation

Vulnerable code when String#unpack's argument is attacker controlled. In the unpack format string argemument, manual sanitization can be done by preventing the number following '@' to overflow to a negative number. See https://dev.to/sqreenio/an-in-depth-look-at-cve-2018-8878-or-why-integer-overflows-are-still-a-thing-1n01 for mitigation details.

Metrics

Weaknesses (2)

CWE-134

CWE-22

Path Traversal

References (21)

Change history (0)

No recorded changes yet.

Sources
CVE.org / MITRE
Status PUBLISHED
Assigner mitre
Published Apr 3, 2018
Updated Aug 5, 2024
Reserved Mar 19, 2018
Link CVE-2018-8778
CISA Vulnrichment
Updated n/a
NVD
Status Modified
Modified Jun 17, 2026
Link CVE-2018-8778
Red Hat
Severity Moderate
Public date Mar 28, 2018
Links CVE-2018-8778 - Bugzilla