CVE-2020-5411 Explained : Impact and Mitigation

Jackson Configuration Allows Code Execution with Unknown "Serialization Gadgets"

Understanding CVE-2020-5411

When configured to enable default typing, Jackson contained a deserialization vulnerability that could lead to arbitrary code execution. Spring Batch configures Jackson with global default typing enabled, potentially allowing arbitrary code execution under specific conditions.

What is CVE-2020-5411?

CVE-2020-5411 is a vulnerability related to Jackson's deserialization process, potentially leading to arbitrary code execution when certain conditions are met within Spring Batch configurations.

The Impact of CVE-2020-5411

This vulnerability could allow malicious actors to execute arbitrary code under specific circumstances, posing a significant security risk to systems utilizing Spring Batch with Jackson configurations.

Technical Details of CVE-2020-5411

Jackson Configuration Vulnerability in Spring Batch

Vulnerability Description

Jackson deserialization vulnerability could lead to arbitrary code execution
Spring Batch's Jackson support with default typing enabled is susceptible to exploitation

Affected Systems and Versions

Product: Spring Batch
Vendor: Spring by VMware
Versions Affected: Custom version 4 less than 4.2.3

Exploitation Mechanism

Exploitation requires leveraging Spring Batch's Jackson support to serialize a job's ExecutionContext
Malicious user gaining write access to the JobRepository's data store can trigger the exploit

Mitigation and Prevention

Protecting Systems from CVE-2020-5411

Immediate Steps to Take

Disable default typing in Jackson configurations within Spring Batch
Implement strict access controls to prevent unauthorized write access to JobRepository

Long-Term Security Practices

Regularly update Spring Batch and Jackson to patched versions
Conduct security audits to identify and mitigate similar vulnerabilities

Patching and Updates

Apply patches provided by Jackson and Spring Batch to address the vulnerability