CVE-2026-63490 PUBLISHED

Handlebars.java: Arbitrary file read in `SpringTemplateLoader` via URL-fragment suffix bypass

Assigner: GitHub_M
Reserved: 16.07.2026 Published: 20.08.2026 Updated: 20.08.2026

Handlebars.java provides logic-less and semantic Mustache templates with Java. Prior to 4.5.3, com.github.jknack.handlebars.springmvc.SpringTemplateLoader resolves attacker-influenced Spring MVC view names through Spring ResourceLoader without the path-containment validation used by other URL-based loaders. In handlebars-springmvc/src/main/java/com/github/jknack/handlebars/springmvc/SpringTemplateLoader.java, a view name using a file: or classpath: URL and ending with the # fragment delimiter places the appended .hbs suffix in the fragment, which FileUrlResource.exists() and URL.openStream() discard. HandlebarsViewResolver in handlebars-springmvc/src/main/java/com/github/jknack/handlebars/springmvc/HandlebarsViewResolver.java then passes the attacker-controlled name to handlebars.compile(), allowing an unauthenticated remote attacker to read files accessible to the JVM when an application exposes a controller with a user-influenced view name. This issue is fixed in version 4.5.3.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CVSS Score: 7.5

Product Status

Vendor jknack
Product handlebars.java
Versions
  • Version < 4.5.3 is affected

References

Problem Types

  • CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') CWE
  • CWE-23: Relative Path Traversal CWE
  • CWE-552: Files or Directories Accessible to External Parties CWE