EUVD-2026-40855

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 createid enabled, Oj::Parserparse is vulnerable to heap corruption via a negative-size memcpy. When a JSON object key is exactly 65,535 bytes long, an integer...

EUVD-2026-40854

Oj Optimized JSON is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.2,Oj::Parserparse is vulnerable to a heap use-after-free when a SAJ/SAJ2 callback mutates the input JSON string during parsing. The C engine holds a raw const byte pointer into the Ruby...

CVE-2026-54898 Oj: Use-After-Free in Oj::Parser SAJ Callback via Input Mutation

Oj Optimized JSON is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.2,Oj::Parserparse is vulnerable to a heap use-after-free when a SAJ/SAJ2 callback mutates the input JSON string during parsing. The C engine holds a raw const byte pointer into the Ruby...

CVE-2026-54898

CVE-2026-54898 (Oj gem) affects the Ruby JSON parser Oj in versions before 3.17.2. The vulnerability occurs when a SAJ/SAJ2 callback mutates the input string during parsing, causing the C engine’s raw pointer into Ruby’s string buffer to become dangling and resulting in a heap use-after-free on t...

CVE-2026-54898 Oj: Use-After-Free in Oj::Parser SAJ Callback via Input Mutation

Oj Optimized JSON is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.2,Oj::Parserparse is vulnerable to a heap use-after-free when a SAJ/SAJ2 callback mutates the input JSON string during parsing. The C engine holds a raw const byte pointer into the Ruby...

CVE-2026-54898

Oj Optimized JSON is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.2,Oj::Parserparse is vulnerable to a heap use-after-free when a SAJ/SAJ2 callback mutates the input JSON string during parsing. The C engine holds a raw const byte pointer into the Ruby...

CVE-2026-54897 Oj : Use-After-Free in Oj::Doc Iterators via Reentrant Close

Oj Optimized JSON is a JSON parser and Object marshaller packaged as a Ruby gem. Prior to 3.17.2, Oj::Doc iterators eachvalue, eachchild, eachleaf were vulnerable to a heap use-after-free. When a Ruby block yielded during iteration calls doc.close or d.close, the document's heap memory is freed...

CVE-2026-54897

Oj Optimized JSON is a JSON parser and Object marshaller packaged as a Ruby gem. Prior to 3.17.2, Oj::Doc iterators eachvalue, eachchild, eachleaf were vulnerable to a heap use-after-free. When a Ruby block yielded during iteration calls doc.close or d.close, the document's heap memory is freed...

CVE-2026-54896

Oj (Optimized JSON) Ruby gem prior to 3.17.2 is affected when operating in object mode; Oj.dump can trigger a heap buffer overflow while serializing Exception objects with a large indent value. The issue stems from allocating a buffer sized for object attributes but not accounting for accumulated...

CVE-2026-54896

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'...

CVE-2026-54896 Oj: Heap Buffer Overflow in Oj.dump Exception Serialization via Large Indent

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'...

CVE-2026-54592 Oj: Stack Buffer Overflow in Oj::Doc#each_child via Deeply Nested Input

Oj Optimized JSON is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.3, Oj::Doceachchild, when invoked recursively over a deeply nested JSON document, overflows a fixed-size stack buffer and aborts the process, leading to DoS. In a two-step chain in...

CVE-2026-54592 Oj: Stack Buffer Overflow in Oj::Doc#each_child via Deeply Nested Input

Oj Optimized JSON is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.3, Oj::Doceachchild, when invoked recursively over a deeply nested JSON document, overflows a fixed-size stack buffer and aborts the process, leading to DoS. In a two-step chain in...

CVE-2026-54592

The CVE-2026-54592 vulnerability affects Oj (Optimized JSON), a Ruby gem JSON parser/marshaller. In versions prior to 3.17.3, Oj::Doc#each_child can overflow a fixed-size stack buffer when recursively traversing deeply nested JSON, causing a DoS. The issue arises from a two-step chain in ext/oj/f...

CVE-2026-54502

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. fillindent in dump.h calls memsetindentstr, ' ', sizetopts-indent without...

CVE-2026-54502

Oj (Optimized JSON) is a Ruby gem that provides a JSON parser and object marshaller. Vulnerability: in versions prior to 3.17.2, Oj.dump can trigger a stack-based buffer overflow when a very large indent value is used. The root cause is fill_indent in dump.h calling memset(indent_str, ' ', (size_...

CVE-2026-54500

Oj (Optimized JSON) is a Ruby gem for JSON parsing/ marshalling. Affects versions prior to 3.17.3 where Oj.load in mode :object reads uninitialized stack memory when a JSON object has a long key (254+ bytes). In ext/oj/intern.c, form_attr() passes an uninitialized stack buffer to rb_intern3(), ca...

CVE-2026-54500 Oj: intern.c form_attr has an uninitialized stack read

Oj Optimized JSON is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.3, Oj.load in :object mode reads uninitialized stack memory and, for long keys, reads out of bounds when parsing a JSON object whose key is 254 bytes or longer. The interned bytes can surfac...

CVE-2026-54500

Oj Optimized JSON is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.3, Oj.load in :object mode reads uninitialized stack memory and, for long keys, reads out of bounds when parsing a JSON object whose key is 254 bytes or longer. The interned bytes can surfac...

CVE-2026-54500 Oj: intern.c form_attr has an uninitialized stack read

Oj Optimized JSON is a JSON parser and Object marshaller packaged as a Ruby gem. In versions prior to 3.17.3, Oj.load in :object mode reads uninitialized stack memory and, for long keys, reads out of bounds when parsing a JSON object whose key is 254 bytes or longer. The interned bytes can surfac...