Skip to content
OpenAdvisories

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.

Affected products

VendorProductAffectedFixed
ohler55 oj < 3.17.2 —

Fixed in Linux distributions

Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.

ReleasePackageFixed inAdvisory
Debian 14 ruby-oj 3.17.3-1 —
Debian 13 ruby-oj 3.16.3-1+deb13u1 —
Debian 12 ruby-oj 3.14.2-1+deb12u1 —
ReleasePackageFixed inAdvisory
Ubuntu 26.10 ruby-oj No fix yet —
Ubuntu 26.04 LTS ruby-oj No fix yet —
Ubuntu 25.10 ruby-oj No fix yet —
Ubuntu 24.04 LTS ruby-oj No fix yet —
Ubuntu 22.04 LTS ruby-oj No fix yet —
Show 4 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
Ubuntu 20.04 LTS ruby-oj No fix yet —
Ubuntu 18.04 LTS ruby-oj No fix yet —
Ubuntu 16.04 LTS ruby-oj No fix yet —
Ubuntu 14.04 LTS ruby-oj No fix yet —

Wolfi

ReleasePackageFixed inAdvisory
Wolfi rolling ruby3.2-fluentd-kubernetes-daemonset-1.19-kinesis 1.19.2.1.1-r5 —
Wolfi rolling ruby3.2-kube-logging-operator-fluentd-outputs +1 6.7.0-r4 —
Wolfi rolling ruby3.3-fluentd-kubernetes-daemonset-1.19-kinesis +2 1.19.3.1.0-r0 —

Public exploits

Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.

Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.

GitHub 1 repository

Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.

Affected packages

EcosystemPackageAffectedFixedRecord
RubyGems oj < 3.17.3 3.17.3 GHSA-9cv6-qcjw-4grx

References