CVE-2022-30633 : Security Advisory and Response

This article provides detailed information about CVE-2022-30633, a vulnerability in the Go standard library affecting the encoding/xml package before versions 1.17.12 and 1.18.4.

Understanding CVE-2022-30633

CVE-2022-30633 involves uncontrolled recursion in the Unmarshal function in encoding/xml, allowing an attacker to trigger a panic due to stack exhaustion by unmarshalling an XML document into a nested Go struct field that uses the 'any' field tag.

What is CVE-2022-30633?

The vulnerability allows for uncontrolled recursion, leading to a stack exhaustion when unmarshalling specific documents in the encoding/xml package of Go versions prior to 1.17.12 and 1.18.4.

The Impact of CVE-2022-30633

An attacker exploiting this vulnerability could cause a denial of service (DoS) condition by triggering a panic due to stack exhaustion, potentially disrupting the availability of the application.

Technical Details of CVE-2022-30633

The technical details of CVE-2022-30633 include:

Vulnerability Description

The vulnerability arises from uncontrolled recursion in the Unmarshal function within the encoding/xml package of affected Go versions, enabling an attacker to exhaust the stack through specific XML document structures.

Affected Systems and Versions

The vulnerability affects Go programming language versions before 1.17.12 and 1.18.4 utilizing the encoding/xml package for XML parsing and struct unmarshalling.

Exploitation Mechanism

By crafting XML documents with nested fields using the 'any' field tag, an attacker can trigger uncontrolled recursion during the unmarshalling process, leading to stack exhaustion and a potential DoS condition.

Mitigation and Prevention

To mitigate the risks associated with CVE-2022-30633, consider the following steps:

Immediate Steps to Take

Update to Go versions 1.17.12 or 1.18.4 to eliminate the vulnerability.
Validate XML input to ensure it conforms to expected structures and limits.

Long-Term Security Practices

Regularly monitor for Go security advisories and updates to stay informed about potential vulnerabilities.
Implement secure coding practices to prevent uncontrolled recursion vulnerabilities in software development.

Patching and Updates

Apply security patches provided by the Go development team promptly to address known security issues and protect systems against exploitation.