CVE-2019-11921 Explained : Impact and Mitigation

Proxygen vulnerability impacting versions prior to v2019.07.22.00 due to Base64 handling issue.

Understanding CVE-2019-11921

A vulnerability in Proxygen versions before v2019.07.22.00 allows unauthorized write access through specially crafted packets.

What is CVE-2019-11921?

In certain Proxygen configurations, an unauthorized write can occur using a specifically designed packet.
The issue stems from incorrect Base64 handling when interpreting malformed binary content in Structured HTTP Headers.

The Impact of CVE-2019-11921

Attackers can exploit this vulnerability to perform out-of-bounds writes, potentially leading to unauthorized access or data manipulation.

Technical Details of CVE-2019-11921

Proxygen vulnerability details and affected systems.

Vulnerability Description

An out-of-bounds write is possible in Proxygen due to improper Base64 handling when parsing malformed binary content in Structured HTTP Headers.

Affected Systems and Versions

Product: Proxygen
Vendor: Facebook
Affected Versions: v2019.07.22.00 and versions preceding it.

Exploitation Mechanism

Attackers can exploit this vulnerability by sending specially crafted packets to trigger unauthorized write access.

Mitigation and Prevention

Steps to mitigate and prevent CVE-2019-11921.

Immediate Steps to Take

Update Proxygen to version v2019.07.22.00 or newer to patch the vulnerability.
Monitor network traffic for any suspicious activities that could indicate exploitation.

Long-Term Security Practices

Regularly update and patch software to prevent known vulnerabilities.
Implement network segmentation to limit the impact of potential attacks.

Patching and Updates

Stay informed about security advisories from vendors like Facebook to apply patches promptly.