CVE-2026-33210 PUBLISHED

Ruby JSON has a format string injection vulnerability

Assigner: GitHub_M
Reserved: 17.03.2026 Published: 20.03.2026 Updated: 20.03.2026

Ruby JSON is a JSON implementation for Ruby. From version 2.14.0 to before versions 2.15.2.1, 2.17.1.2, and 2.19.2, a format string injection vulnerability can lead to denial of service attacks or information disclosure, when the allow_duplicate_key: false parsing option is used to parse user supplied documents. This issue has been patched in versions 2.15.2.1, 2.17.1.2, and 2.19.2.

Metrics

CVSS 4.0

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N
CVSS Score: 8.3

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	Low	Confidentiality	None
Attack Complexity	Low	Integrity	None	Integrity	None
Attack Requirements	Present	Availability	High	Availability	None
Privileges Required	None
User Interaction	None

CVSS 4.0

Product Status

Vendor	ruby
Product	json
Versions	Version >= 2.14.0, < 2.15.2.1 is affected Version >= 2.16.0, < 2.17.1.2 is affected Version >= 2.18.0, < 2.19.2 is affected

References

https://github.com/ruby/json/security/advisories/GHSA-3m6g-2423-7cp3

Problem Types

CWE-134: Use of Externally-Controlled Format String CWE