CVE-2021-3822 is a high-severity (CVSS 7.5) CWE-1333 vulnerability in jsoneditor. 1 public exploit reference exists, so weaponization risk is real. A fix is available for jsoneditor — see the affected versions and patch details below.
Regular Expression Denial of Service in jsoneditor
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2021-3822 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,987 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
jsoneditornpmDescription
JSON Editor is a web-based tool to view, edit, format, and validate JSON. It has various modes such as a tree editor, a code editor, and a plain text editor. The jsoneditor package is vulnerable to ReDoS (regular expression denial of service). An attacker that is able to provide a crafted element as input to the getInnerText function may cause an application to consume an excessive amount of CPU. Below pinned line using vulnerable regex.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | jsoneditor | all versions | 9.5.6npm install jsoneditor@9.5.6 |
Affected Products
jsoneditorjsoneditoronlineResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for jsoneditor, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update jsoneditor to 9.5.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-3822 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.
Frequently Asked Questions
Is CVE-2021-3822 in your dependencies?
Find it across npm, including transitive dependencies.