Arbitrary Bytecode Generation Vulnerability in Apache Commons BCEL
Summary
CVE-2022-42920: Apache Commons BCEL has a number of APIs that would normally only allow changing specific class characteristics. Affects bcel across 2 version ranges.
< 6.5.0-1+deb11u1
< cf520ef45064c8fa4f43717ecc789d5a4f6b0d57
Fixed in 6.5.0-1+deb11u1. How to fix ↓
Check if this vulnerability affects your application
Upload a manifest or SBOM and we'll show whether you're affected, plus every other risky package in the same scan.
No signup required · Results in about 60 seconds
Background
Apache Commons BCEL (Byte Code Engineering Library) is a Java library that allows developers to analyze, create, and manipulate Java bytecode. It provides a range of APIs that enable users to modify class files and generate new bytecode dynamically. However, due to a critical vulnerability, certain APIs can be exploited to produce arbitrary bytecode, posing significant security risks to applications that utilize this library.
Vulnerability Detail
The vulnerability identified as CVE-2022-42920 arises from an out-of-bounds writing issue in Apache Commons BCEL. This flaw allows attackers to manipulate specific class characteristics through the library's APIs, leading to the potential generation of arbitrary bytecode. If an application passes attacker-controllable data to these APIs, it can result in severe consequences, including unauthorized access, data corruption, or execution of malicious code. The CVSS score for this vulnerability is 9.8, indicating a critical level of severity.
How To Fix
Minimum fixed version
6.5.0-1+deb11u1
This is the first release that contains the fix.
sudo apt-get install --only-upgrade bcelTip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
If immediate updating is not feasible, consider implementing input validation to sanitize any data passed to the BCEL APIs. This can help mitigate the risk of exploitation until a proper update can be applied. For example, you can add checks to ensure that the input data conforms to expected formats and ranges before processing it with BCEL.
Conclusion
The CVE-2022-42920 vulnerability in Apache Commons BCEL poses a significant risk due to its potential for arbitrary bytecode generation. It is crucial for developers using this library to update to the latest version to protect their applications from exploitation. Implementing input validation can serve as a temporary measure while transitioning to the updated library.
See every vulnerability recorded for bcel →
FAQ
CVE-2022-42920 is a vulnerability in Apache Commons BCEL that allows for arbitrary bytecode generation due to an out-of-bounds writing issue.
If your application uses Apache Commons BCEL and passes untrusted data to its APIs, an attacker could exploit this vulnerability to execute arbitrary code or manipulate bytecode.
It is recommended to update to Apache Commons BCEL version 6.6.0 or later to mitigate this vulnerability.
Implementing input validation to sanitize data before it is passed to BCEL APIs can serve as a temporary workaround until an update is applied.
You can use tools like Vulert, which monitors and alerts for open-source vulnerabilities in your software using just a manifest file like package-lock.json. You can also check your application against known vulnerabilities using the Vulert playground.
Related vulnerabilities
Recent vulnerabilities recorded for bcel.
