CVE-2026-54900
Oj: Negative-Size memcpy in Oj::Parser create_id Attribute Handling
- State
- Published
- Severity
- 6.3 Medium
- Published
- Jun 30, 2026
- Updated
- Jul 1, 2026
- Reserved
- Jun 16, 2026
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 6.3 Medium | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N | GitHub_M |
Weaknesses
Affected Products
| Product | Versions |
|---|---|
ojohler55 |
|
References
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