CVE-2025-59340: Jinjava Jinjava Has Sandbox Bypass Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-m49c-g9wr-hv6v",
  "modified" : "2026-07-31T22:15:57Z",
  "published" : "2025-09-17T19:56:21Z",
  "aliases" : [ "CVE-2025-59340" ],
  "summary" : "jinjava has Sandbox Bypass via JavaType-Based Deserialization",
  "details" : "### Summary\n\njinjava’s current sandbox restrictions prevent direct access to dangerous methods such as `getClass()`, and block instantiation of Class objects. However, these protections can be bypassed.\n\nBy 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.\n\nAs 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).\n\n### Details\n\njinjava templates expose a built-in variable `____int3rpr3t3r____`, which provides direct access to the jinjavaInterpreter instance.\nThis variable was previously abused and protections were added to prevent call method from `JinjavaInterpreter` instances (see [Add interpreter to blacklist](https://github.com/HubSpot/jinjava/commit/1b9aaa4b420c58b4a301cf4b7d26207f1c8d1165)).\nHowever, interacting with the properties of `JinjavaInterpreter` instances remains [unrestricted](https://github.com/HubSpot/jinjava/blob/jinjava-2.8.0/src/main/java/com/hubspot/jinjava/el/ext/JinjavaBeanELResolver.java#L80-L84).\n\nFrom `____int3rpr3t3r____`, it is possible to traverse to the `config` field, which exposes an ObjectMapper. By invoking `readValue(String content, JavaType valueType)` on this ObjectMapper, an attacker can instantiate arbitrary classes specified via `JavaType`.\n\nAlthough jinjava explicitly restricts dangerous classes such as `Class`, `ClassLoader`, and so on inside `JinjavaBeanELResolver`, the `JavaType` class itself is [not restricted](https://github.com/HubSpot/jinjava/blob/jinjava-2.8.0/src/main/java/com/hubspot/jinjava/el/ext/JinjavaBeanELResolver.java#L246-L262). \n\nAs a result, an attacker can leverage `JavaType` construction (`constructFromCanonical`) to instantiate semi-arbitrary classes without directly calling restricted methods.\n\nThis allows sandbox escape and the creation of powerful primitives. \n\n### Impact\nEscape the Jinjava sandbox and instantiate a wide range of classes using JavaType.\nThis capability can be used to read arbitrary files and to perform full read SSRF by creating network-related objects.\nIn certain environments, depending on the available classes, this primitive can even lead to complete remote code execution.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "com.hubspot.jinjava:jinjava"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "2.8.0"
      }, {
        "fixed" : "2.8.1"
      } ]
    } ],
    "versions" : [ "2.8.0" ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "com.hubspot.jinjava:jinjava"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "2.7.0"
      }, {
        "fixed" : "2.7.5"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/HubSpot/jinjava/security/advisories/GHSA-m49c-g9wr-hv6v"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-59340"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/github/advisory-database/pull/8141"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/HubSpot/jinjava/commit/66df351e7e8ad71ca04dcacb4b65782af820b8b1"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/HubSpot/jinjava"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/HubSpot/jinjava/releases/tag/jinjava-2.7.5"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/HubSpot/jinjava/releases/tag/jinjava-2.8.1"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-1336" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-09-17T19:56:21Z",
    "nvd_published_at" : "2025-09-17T20:15:36Z"
  }
}