CVE-2021-44790 : What You Need to Know

Possible buffer overflow when parsing multipart content in mod_lua of Apache HTTP Server 2.4.51 and earlier

Understanding CVE-2021-44790

What is CVE-2021-44790?

A carefully crafted request body can cause a buffer overflow in the mod_lua multipart parser (r:parsebody() called from Lua scripts). This vulnerability affects Apache HTTP Server 2.4.51 and earlier, potentially allowing for exploitation.

The Impact of CVE-2021-44790

This vulnerability poses a high risk due to the potential buffer overflow, which may lead to unauthorized access, denial of service, or potentially arbitrary code execution.

Technical Details of CVE-2021-44790

Vulnerability Description

A buffer overflow in the mod_lua multipart parser can result from a specially crafted request body, impacting Apache HTTP Server 2.4.51 and prior versions.

Affected Systems and Versions

Vendor: Apache Software Foundation
Product: Apache HTTP Server
Versions Affected: Apache HTTP Server 2.4 up to version 2.4.51 (inclusive)

Exploitation Mechanism

The vulnerability can be exploited by sending a malicious multipart content request, triggering the buffer overflow in the mod_lua parser.

Mitigation and Prevention

Immediate Steps to Take

Apply the latest security patches provided by Apache Software Foundation.
Monitor official sources for updates on this vulnerability.

Long-Term Security Practices

Regularly update and patch Apache HTTP Server to secure against known vulnerabilities.
Implement network controls and monitoring to detect and prevent malicious requests.
Conduct regular security assessments and audits of web server configurations.

Patching and Updates

Stay informed about security advisories from Apache Software Foundation and promptly apply patches to address CVE-2021-44790.