CVE-2026-54502
MediumCVSS 6.3Exploitation Probability (EPSS)
Low risk17th percentile — higher than 17% of all known CVEs
Summary
A stack-based buffer overflow vulnerability was found in the Oj (Optimized JSON) library for Ruby in the Oj.dump method. The issue occurs when a large :indent value is provided, causing a 2 GB write to the stack and process crash.
Risk Assessment
An attacker can exploit this vulnerability to cause a denial of service (DoS) by crashing the application using the Oj library with unsafe parameters.
Recommendation
Immediately update the Oj library to version 3.17.2 or later, which includes a fix for the buffer overflow.
Original NVD description (English source)
Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.2, Oj.dump is vulnerable to a stack-based buffer overflow when a large :indent value is provided by the developer. fill_indent in dump.h calls memset(indent_str, ' ', (size_t)opts->indent) without validating the size. When opts->indent is set to INT_MAX (2,147,483,647), the (size_t) cast preserves the large value and memset writes 2 GB into the stack-allocated out buffer (4,184 bytes), corrupting the stack and crashing the process. This issue has been fixed in version 3.17.2.