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Overview

Affected versions of this package are vulnerable to XML External Entity (XXE) Injection. The XML parsers used by XMLBeans did not set the properties needed to protect the user from malicious XML input. Vulnerabilities include possibilities for XML Entity Expansion attacks.

Details

XXE Injection is a type of attack against an application that parses XML input. XML is a markup language that defines a set of rules for encoding documents in a format that is both human-readable and machine-readable. By default, many XML processors allow specification of an external entity, a URI that is dereferenced and evaluated during XML processing. When an XML document is being parsed, the parser can make a request and include the content at the specified URI inside of the XML document.

Attacks can include disclosing local files, which may contain sensitive data such as passwords or private user data, using file: schemes or relative paths in the system identifier.

For example, below is a sample XML document, containing an XML element- username.

<xml>
<?xml version="1.0" encoding="ISO-8859-1"?>
   <username>John</username>
</xml>

An external XML entity - xxe, is defined using a system identifier and present within a DOCTYPE header. These entities can access local or remote content. For example the below code contains an external XML entity that would fetch the content of /etc/passwd and display it to the user rendered by username.

<xml>
<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE foo [
   <!ENTITY xxe SYSTEM "file:///etc/passwd" >]>
   <username>&xxe;</username>
</xml>

Other XXE Injection attacks can access local resources that may not stop returning data, possibly impacting application availability and leading to Denial of Service.

Remediation

Upgrade org.apache.xmlbeans:xmlbeans to version 3.0.0 or higher.

References

• Apache CVE Announcement
• GitHub Release
• JIra Issue

Overview

com.h2database:h2 is a database engine

Affected versions of this package are vulnerable to Remote Code Execution (RCE). H2 Console allows loading of custom classes from remote servers through JNDI. This can lead to code execution

If remote access was enabled explicitly and some protection method (such as security constraint) are not set, an intruder can load their own custom class and execute their code in a process using H2 Console (a H2 Server process or a web server with H2 Console servlet).

Note: It should be noted that H2 Console doesn't accept remote connections by default.

Workarounds

• H2 Console should never be available to untrusted users.

• -webAllowOthers is a dangerous setting that should be avoided.

• H2 Console Servlet deployed on a web server can be protected with a security constraint: https://h2database.com/html/tutorial.html#usingH2ConsoleServlet If webAllowOthers is specified, you need to uncomment and edit and as necessary. See documentation of your web server for more details.

All these workaround are mitigatory and unlikely to prevent all attack vectors, upgrade to a fixed version for full remediation.

Remediation

Upgrade com.h2database:h2 to version 2.0.206 or higher.

References

• GItHub Advisory
• GitHub Commit
• The JNDI Strikes Back – Unauthenticated RCE in H2 Database Console

Overview

com.h2database:h2 is a database engine

Affected versions of this package are vulnerable to XML External Entity (XXE) Injection via the org.h2.jdbc.JdbcSQLXML class object, when it receives parsed string data from org.h2.jdbc.JdbcResultSet.getSQLXML() method. If it executes the getSource() method when the parameter is DOMSource.class it will trigger the vulnerability.

Details

XXE Injection is a type of attack against an application that parses XML input. XML is a markup language that defines a set of rules for encoding documents in a format that is both human-readable and machine-readable. By default, many XML processors allow specification of an external entity, a URI that is dereferenced and evaluated during XML processing. When an XML document is being parsed, the parser can make a request and include the content at the specified URI inside of the XML document.

Attacks can include disclosing local files, which may contain sensitive data such as passwords or private user data, using file: schemes or relative paths in the system identifier.

For example, below is a sample XML document, containing an XML element- username.

<xml>
<?xml version="1.0" encoding="ISO-8859-1"?>
   <username>John</username>
</xml>

An external XML entity - xxe, is defined using a system identifier and present within a DOCTYPE header. These entities can access local or remote content. For example the below code contains an external XML entity that would fetch the content of /etc/passwd and display it to the user rendered by username.

<xml>
<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE foo [
   <!ENTITY xxe SYSTEM "file:///etc/passwd" >]>
   <username>&xxe;</username>
</xml>

Other XXE Injection attacks can access local resources that may not stop returning data, possibly impacting application availability and leading to Denial of Service.

Remediation

Upgrade com.h2database:h2 to version 2.0.202 or higher.

References

• GitHub Commit
• GitHub Issue
• GitHub PR

Overview

org.apache.velocity:velocity-engine-core is a template engine written in Java.

Affected versions of this package are vulnerable to Arbitrary Code Execution. An attacker that is able to modify Velocity templates may execute arbitrary Java code or run arbitrary system commands with the same privileges as the account running the Servlet container. This applies to applications that allow untrusted users to upload/modify velocity templates running Apache Velocity Engine.

Note Users of org.apache.velocity:velocity should update to org.apache.velocity:velocity-engine-core version 2.3 to mitigate this vulnerability.

Remediation

Upgrade org.apache.velocity:velocity-engine-core to version 2.3 or higher.

References

• Apache Security Advisory
• GitHub PR
• GitHub Security Labs

Overview

com.h2database:h2 is a database engine

Affected versions of this package are vulnerable to Remote Code Execution (RCE). It provides a web console for managing the database, and by default it does not have a password set. The CREATE ALIAS function calls Java code, allowing an attacker to execute arbitrary Java code on projects running the h2 database.

NOTE: To be remotely exploitable, the affected application must be configured with the non-default setting webAllowOthers=true, either in a config file or as a parameter passed in when the servlet is invoked. The vulnerability can be avoided by setting a password on the database and/or restricting access to localhost using the above setting.

PoC

CREATE ALIAS REVERSE AS $$ String reverse(String s) { return new StringBuilder(s).reverse().toString(); } $$;
CALL REVERSE('Test');

Remediation

There is no fixed version for com.h2database:h2.

References

• Datomic Blog
• Datomic Security Advisory
• Exploit DB
• GitHub Issue
• Matheus Bernardes' Blog

Overview

Affected versions of this package are vulnerable to Allocation of Resources Without Limits or Throttling. An attacker can cause indefinite amounts of memory to be used by inputting a string of modest size. This can lead to a Denial of Service.

PoC

package orgjsonbug;

import org.json.JSONObject;

/**
 * Illustrates a bug in JSON-Java.
 */
public class Bug {
  private static String makeNested(int depth) {
    if (depth == 0) {
      return "{\"a\":1}";
    }
    return "{\"a\":1;\t\0" + makeNested(depth - 1) + ":1}";
  }

  public static void main(String[] args) {
    String input = makeNested(30);
    System.out.printf("Input string has length %d: %s\n", input.length(), input);
    JSONObject output = new JSONObject(input);
    System.out.printf("Output JSONObject has length %d: %s\n", output.toString().length(), output);
  }
}

Remediation

Upgrade org.json:json to version 20231013 or higher.

References

• GitHub Commit
• GitHub Issue
• GitHub Issue

Overview

Affected versions of this package are vulnerable to Denial of Service (DoS) in the XML.toJSONObject component via crafted JSON or XML data.

Details

Denial of Service (DoS) describes a family of attacks, all aimed at making a system inaccessible to its intended and legitimate users.

Unlike other vulnerabilities, DoS attacks usually do not aim at breaching security. Rather, they are focused on making websites and services unavailable to genuine users resulting in downtime.

One popular Denial of Service vulnerability is DDoS (a Distributed Denial of Service), an attack that attempts to clog network pipes to the system by generating a large volume of traffic from many machines.

When it comes to open source libraries, DoS vulnerabilities allow attackers to trigger such a crash or crippling of the service by using a flaw either in the application code or from the use of open source libraries.

Two common types of DoS vulnerabilities:

• High CPU/Memory Consumption- An attacker sending crafted requests that could cause the system to take a disproportionate amount of time to process. For example, commons-fileupload:commons-fileupload.

• Crash - An attacker sending crafted requests that could cause the system to crash. For Example, npm ws package

Remediation

Upgrade org.json:json to version 20230227 or higher.

References

• GitHub Commit
• GitHub Commit
• GitHub Issue
• GitHub Issue

Overview

org.jsoup:jsoup is a Java library for working with real-world HTML. It provides a very convenient API for extracting and manipulating data, using the best of DOM, CSS, and jquery-like methods. jsoup implements the WHATWG HTML5 specification, and parses HTML to the same DOM as modern browsers do.

Affected versions of this package are vulnerable to Denial of Service (DoS). If the parser is run on user supplied input, an attacker may supply content that causes the parser to get stuck (loop indefinitely until cancelled), to complete more slowly than usual, or to throw an unexpected exception. This effect may support a denial of service attack. There are a few available workarounds. Users may rate limit input parsing, limit the size of inputs based on system resources, and/or implement thread watchdogs to cap and timeout parse runtimes.

Details

Denial of Service (DoS) describes a family of attacks, all aimed at making a system inaccessible to its intended and legitimate users.

Unlike other vulnerabilities, DoS attacks usually do not aim at breaching security. Rather, they are focused on making websites and services unavailable to genuine users resulting in downtime.

One popular Denial of Service vulnerability is DDoS (a Distributed Denial of Service), an attack that attempts to clog network pipes to the system by generating a large volume of traffic from many machines.

When it comes to open source libraries, DoS vulnerabilities allow attackers to trigger such a crash or crippling of the service by using a flaw either in the application code or from the use of open source libraries.

Two common types of DoS vulnerabilities:

• High CPU/Memory Consumption- An attacker sending crafted requests that could cause the system to take a disproportionate amount of time to process. For example, commons-fileupload:commons-fileupload.

• Crash - An attacker sending crafted requests that could cause the system to crash. For Example, npm ws package

Remediation

Upgrade org.jsoup:jsoup to version 1.14.2 or higher.

References

• JSoup Release