CVE-2025-59340 | jinjava Sandbox Bypass via JavaType-Based Deserialization
jinjava is a Java-based template engine based on django template syntax, adapted to render jinja templates. Priori to 2.8.1, by using mapper.getTypeFactory().constructFromCanonical(), it is possible to instruct the underlying ObjectMapper to deserialize attacker-controlled input into arbitrary classes. This enables the creation of semi-arbitrary class instances without directly invoking restricted methods or class literals. As a result, an attacker can escape the sandbox and instantiate classes such as java.net.URL, opening up the ability to access local files and URLs(e.g., file:///etc/passwd). With further chaining, this primitive can potentially lead to remote code execution (RCE). This vulnerability is fixed in 2.8.1.
Conclusion & alert: CVE-2025-59340 is rated High Risk (67.4/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 1.27%).Mandatory action: High exploitation likelihood—assess exposure and prioritize remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
Exploit prediction scoring system (EPSS) score for CVE-2025-59340
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).