Vulnerability library
Security checkJanuary 08, 2026

Preact has JSON VNode Injection issue

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High severitynpmpreact

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Description

Vulnerability Type: HTML Injection via JSON Type Confusion

Affected Versions: Preact 10.26.5 through 10.28.1

Severity: Low to Medium (see below)

Recommendation

Update the preact package to the latest compatible version. Followings are version details:

  • Affected version(s): **>= 10.28.0, < 10.28.2 >= 10.27.0, < 10.27.3 >= 10.26.5, < 10.26.10**
  • Patched version(s): **10.28.2 10.27.3 10.26.10**

References

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Related Issues

See something that needs correcting? Let us knowUpdated January 08, 2026