CVE-2026-63490
Handlebars.java: Arbitrary file read in `SpringTemplateLoader` via URL-fragment suffix bypass
Impact
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.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| maven | com.github.jknack:handlebars-springmvc | < 4.5.3 | 4.5.3 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-g29j-rwfv-h99w
- https://github.com/jknack/handlebars.java/security/advisories/GHSA-g29j-rwfv-h99w
- https://nvd.nist.gov/vuln/detail/CVE-2026-63490
- https://github.com/jknack/handlebars.java/commit/61f43423a337b87db5fec1fe59f0725aaaa38df5
- https://github.com/jknack/handlebars.java/releases/tag/v4.5.3