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

Summary 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 string's internal buffer. If a callback e.g. hashstart resizes the string — for example by calling...

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

Summary Oj::Doc iterators eachvalue, eachchild, eachleaf are 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 while the C iterator is still running. When control returns from the block, the iterator rea...

Use After Free

Overview Affected versions of this package are vulnerable to Use After Free in the eachvalue, eachchild, or eachleaf iterators when a Ruby block executed during iteration calls the close method on the document or its child nodes. An attacker can cause memory corruption by invoking close within a...

GHSA-FM7P-MPRW-WJM9 Oj: intern.c form_attr (uninitialized stack read)

Summary 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 surface to the caller, disclosing process stack memory. Details In ext/oj/intern.c, formattr handles the...

GHSA-2CW7-V8FF-P88R Oj: Use-After-Free in Oj::Parser Symbol Key Cache Toggle

Summary Disabling symbolkeys on a reused Oj::Parser instance triggers a heap use-after-free. When symbolkeys is toggled from true to false, optsymbolkeysset frees the internal key cache cachefree but does not clear the pointer. The next parse call reads from the freed cache via cacheintern,...

CVE-2026-49342

YARD is a documentation generation tool for the Ruby programming language. Prior to version 0.9.44, YARD's static cache lookup reads a request path before the router's path cleanup runs. When a server is configured with a document root, a traversal path such as /../yard-cache-secret.html is joine...

GHSA-P67V-3W7G-WJG7 Nokogiri: Possible Use-After-Free when directly using `NokogirI::XML::XPathContext` beyond document lifetime

Summary Nokogiri::XML::XPathContext did not keep its source document alive for garbage collection. If an XPathContext outlived its document and the document was collected, evaluating an XPath expression could read invalid memory and potentially segfault. This is only reachable when application co...

Nokogiri: Possible Use-After-Free when setting `Document#root=` to an invalid node type

Summary Nokogiri::XML::Documentroot= validated only that the new root was a Nokogiri::XML::Node, allowing a DTD node to be set as the document root. The result is a heap use-after-free during garbage collection or finalization, leading to an invalid memory read or potentially a segfault. Nokogiri...

GHSA-5PRR-V3J2-97MH Nokogiri: Possible Out-of-Bounds Read in `Nokogiri::XML::NodeSet#[]`

Summary Nokogiri::XML::NodeSet and its alias slice checked the requested index against the node set's bounds using a 32-bit-truncated copy of the index. A large negative index could pass the check and then be used at full width, reading outside the node set's storage. On CRuby this is an...

XML External Entity (XXE) Injection

Overview nokogiri is a gem for parsing HTML, XML, SAX, and Reader. Affected versions of this package are vulnerable to XML External Entity XXE Injection in the Nokogiri::XML::Schema when the NONET parse option is not correctly enforced on JRuby. An attacker can access external network resources b...

PT-2026-51019

Name of the Vulnerable Software and Affected Versions YARD versions prior to 0.9.44 Description YARD is a documentation generation tool for the Ruby programming language. The static cache lookup reads a request path before the router's path cleanup process occurs. When a server is configured with...

PT-2026-51084

Name of the Vulnerable Software and Affected Versions oj gem affected versions not specified Description A heap use-after-free occurs in Oj::Parserparse when a SAJ/SAJ2 callback mutates the input JSON string during the parsing process. The C engine maintains a raw pointer to the Ruby string's...

PT-2026-51085

Name of the Vulnerable Software and Affected Versions Oj versions prior to 3.17.2 Description A heap use-after-free occurs when disabling symbol keys on a reused Oj::Parser instance. When the symbol keys setting is changed from true to false, the opt symbol keys set function frees the internal ke...

RHEL 9 : ruby:3.3 (RHSA-2026:26655)

The remote Redhat Enterprise Linux 9 host has packages installed that are affected by a vulnerability as referenced in the RHSA-2026:26655 advisory. Ruby is an extensible, interpreted, object-oriented, scripting language. It has features to process text files and to perform system management task...

Concurrent Ruby - `AtomicReference#update` livelocks when the stored value is `Float::NAN`

Summary Concurrent::AtomicReferenceupdate can enter a permanent busy retry loop when the current value is Float::NAN. The issue is caused by the interaction between: - AtomicReferenceupdate, which retries until compareandsetoldvalue, newvalue succeeds. - Numeric compareandset, which checks old ==...

PT-2026-51090

Name of the Vulnerable Software and Affected Versions concurrent-ruby versions prior to 1.3.7 Description The Concurrent::AtomicReferenceupdate function can enter a permanent busy retry loop when the current value is Float::NAN. This occurs due to the interaction between AtomicReferenceupdate,...

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

Summary 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 string's internal buffer. If a callback e.g. hashstart resizes the string — for example by calling...

Oj - intern.c form_attr (uninitialized stack read)

Summary 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 surface to the caller, disclosing process stack memory. Impact Information disclosure of process stack memor...

PT-2026-51091

Name of the Vulnerable Software and Affected Versions concurrent-ruby versions prior to 1.3.7 Description Concurrent::ReentrantReadWriteLock can incorrectly grant a write lock after a single thread acquires the read lock 32,768 times. The lock manages a thread's local read and write hold counts...

PT-2026-51083

Name of the Vulnerable Software and Affected Versions Oj versions prior to 3.17.2 Description Oj::Doc iterators each value, each child, each leaf are subject to a heap use-after-free. This occurs when a Ruby block yielded during iteration calls doc.close or d.close, causing the document's heap...