jsonschema2pojo, Buffer Overflow, CVE-2025-XXXX (Moderate)

How the CVE Works:

The vulnerability in jsonschema2pojo (CVE-2025-XXXX) stems from improper bounds checking in the `SchemaRule.java` component when processing JSON schema files. A stack-based buffer overflow occurs in the `apply()` function due to unchecked input size during schema validation. Attackers can craft malicious JSON files containing oversized nested schema definitions, causing memory corruption. Since the application fails to enforce proper size restrictions, excessive recursion or large payloads overwrite adjacent stack memory, potentially allowing arbitrary code execution. Local exploitation is required, limiting impact but enabling privilege escalation if the tool runs with elevated permissions.

DailyCVE Form:

Platform: jsonschema2pojo
Version: <= 1.2.2
Vulnerability: Buffer Overflow
Severity: Moderate
Date: 2025-04-14

What Undercode Say:

Exploitation:

1. Payload Crafting:

{
"$ref": "/definitions/recursive",
"definitions": {
"recursive": { "$ref": "/definitions/recursive" }
}
}

2. Trigger Overflow:

java -jar jsonschema2pojo.jar -T JSON -s payload.json

Protection:

1. Input Validation Patch:

if (schemaDepth > MAX_DEPTH) throw new SchemaException("Depth limit exceeded");

2. Memory Protections:

Enable ASLR and stack canaries
sysctl -w kernel.randomize_va_space=2

Detection:

1. Log Monitoring:

grep -r "StackOverflowError" /var/log/jsonschema2pojo

2. Static Analysis:

semgrep --config p/java-buffer-overflow SchemaRule.java

Mitigation Commands:

1. Downgrade:

mvn org.jsonschema2pojo:jsonschema2pojo-maven-plugin:1.2.1

2. Sandboxing:

firejail --private java -jar jsonschema2pojo.jar