Use of Externally-Controlled Format String Affecting json package, versions >=2.14.0, <2.15.2.1>=2.16.0, <2.17.1.2>=2.18.0, <2.19.2
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published19 Mar 2026
- disclosed19 Mar 2026
- creditDavidKorczynski
Introduced: 19 Mar 2026
CVE-2026-33210 (opens in a new tab)How to fix?
Upgrade json to version 2.15.2.1, 2.17.1.2, 2.19.2 or higher.
Overview
json is a JSON implementation as a Ruby extension in C.
Affected versions of this package are vulnerable to Use of Externally-Controlled Format String in JSON.parse(doc, allow_duplicate_key: false). An attacker can cause denial of service or disclose sensitive information via malicious format strings. This is only exploitable if the allow_duplicate_key: false option is explicitly enabled.