CVE-2026-54900
Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem.
Overview
CVE-2026-54900 is a known-severity vulnerability. It was published on July 1, 2026.
Technical description
Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.2, when in usual mode with create_id enabled, Oj::Parser#parse is vulnerable to heap corruption via a negative-size memcpy. When a JSON object key is exactly 65,535 bytes long, an integer truncation in form_attr (usual.c:63) converts the length to -1 before passing it to memcpy. This causes memcpy to copy SIZE_MAX bytes (interpreted as a huge size_t), corrupting heap memory and crashing the process. The issue has been fixed in version 3.17.2.
Remediation
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
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Frequently asked questions
What is CVE-2026-54900?
CVE-2026-54900 is a known-severity vulnerability. It was published on July 1, 2026.
How severe is CVE-2026-54900?
CVSS score information is not yet available for this vulnerability. Check back as the CVE record is updated by NVD analysts.
How do I fix or remediate CVE-2026-54900?
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-54900?
CyberStrike is an open-source, AI-augmented pentesting engine. Rather than flag a version number, it tests whether an issue like CVE-2026-54900 is actually reachable in your own applications and APIs, then verifies each finding before reporting it. That tells you if the weakness is a real, exploitable risk in your environment or a false positive you can safely deprioritize.