Access of Resource Using Incompatible Type ('Type Confusion') Affecting preact package, versions >=10.26.5 <10.26.10>=10.27.0 <10.27.3>=10.28.0 <10.28.2
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
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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- published8 Jan 2026
- disclosed7 Jan 2026
- creditYoungGeun Choi
Introduced: 7 Jan 2026
CVE-2026-22028 (opens in a new tab)How to fix?
Upgrade preact to version 10.26.10, 10.27.3, 10.28.2 or higher.
Overview
preact is a fast 3kB alternative to React with the same modern API.
Affected versions of this package are vulnerable to Access of Resource Using Incompatible Type ('Type Confusion') during rendering in the vnode constructor. An attacker can inject arbitrary HTML or execute scripts by supplying specially crafted JSON objects that are incorrectly interpreted as valid VNodes when unsanitized, unvalidated user input is passed directly into the render tree.
Note:
This is only exploitable if applications pass unmodified, unsanitized values from user-modifiable data sources directly into the render tree, assume these values are strings while the data source could return JavaScript objects, and the data source fails to perform type sanitization or is compromised.
##Workaround
This vulnerability can be mitigated by validating input types, enforcing strict type contracts at API boundaries, casting or validating network data before rendering, sanitizing external data, and implementing a strict Content Security Policy (CSP) to prevent inline script execution.