Improper Encoding or Escaping of Output Affecting github.com/vapor/leaf-kit package, versions <1.14.2
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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- published18 Mar 2026
- disclosed16 Mar 2026
- creditiCMDdev
Introduced: 16 Mar 2026
NewCVE-2026-28499 (opens in a new tab)How to fix?
Upgrade vapor/leaf-kit to version 1.14.2 or higher.
Overview
vapor/leaf-kit is an an expressive, performant, and extensible templating language built for Swift.
Affected versions of this package are vulnerable to Improper Encoding or Escaping of Output in the htmlEscaped process. An attacker can inject and execute arbitrary scripts in the context of the rendered page by supplying specially crafted input within arrays or dictionaries that is not properly escaped during template rendering.