CVE-2026-54896
Oj: Heap Buffer Overflow in Oj.dump Exception Serialization via Large Indent
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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 object mode, Oj.dump is vulnerable to a heap buffer overflow when serializing Exception objects with a large :indent value. The serializer allocates a buffer sized for the object's attributes but does not account for the indent bytes added on each write. With indent: 5000, the accumulation of 5,000-byte indent strings overflows the 13,150-byte heap allocation, corrupting adjacent heap memory. This issue has been fixed in version 3.17.2.
Remediation
No guide yetNo remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.
References (1)
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