CVE-2023-22465 : What You Need to Know

This CVE involves a vulnerability in Http4s, a Scala interface for HTTP services, where the

User-Agent

and

Server

header parsers are prone to fatal errors in certain inputs.

Understanding CVE-2023-22465

This section provides an overview of the CVE-2023-22465 vulnerability affecting Http4s.

What is CVE-2023-22465?

CVE-2023-22465 is classified under CWE-20: Improper Input Validation. It affects Http4s versions ranging from >= 0.1.0 to < 0.21.34, >= 0.22.0 to < 0.22.15, >= 0.23.0 to < 0.23.17, and >= 1.0.0-M1 to < 1.0.0-M38. The vulnerability arises due to fatal errors occurring when parsing certain inputs in the

User-Agent

and

Server

header parsers.

The Impact of CVE-2023-22465

The CVSS v3.1 base score for CVE-2023-22465 is 7.5, categorizing it as a high severity issue. The attack complexity is low, and it can lead to high availability impact. While confidentiality and integrity impacts are none, privileges are not required for exploitation.

Technical Details of CVE-2023-22465

This section delves deeper into the technical aspects of CVE-2023-22465 in Http4s.

Vulnerability Description

The vulnerability in Http4s arises from the lazily parsed modeled headers, specifically affecting services that request typed headers explicitly. The fatal error occurs in the parsing of

User-Agent

and

Server

headers before the respective fixes are implemented in versions 0.21.34, 0.22.15, 0.23.17, and 1.0.0-M38. A workaround suggested is to use the weakly typed header interface.

Affected Systems and Versions

Http4s versions >= 0.1.0 to < 0.21.34, >= 0.22.0 to < 0.22.15, >= 0.23.0 to < 0.23.17, and >= 1.0.0-M1 to < 1.0.0-M38 are impacted by this vulnerability.

Exploitation Mechanism

The vulnerability can be exploited when certain inputs trigger fatal errors in the

User-Agent

and

Server

header parsers due to the way modeled headers are lazily parsed in Http4s.

Mitigation and Prevention

In response to CVE-2023-22465, it is crucial to implement mitigation strategies to safeguard systems and prevent potential exploitation.

Immediate Steps to Take

Update Http4s to the fixed versions - 0.21.34, 0.22.15, 0.23.17, or 1.0.0-M38 to eliminate the vulnerability.
Utilize the weakly typed header interface as a temporary workaround to reduce the risk of exploitation.

Long-Term Security Practices

Regularly monitor and apply security patches and updates to mitigate emerging vulnerabilities promptly.
Conduct thorough testing of HTTP services to ensure proper input validation procedures are in place.

Patching and Updates

Stay informed about security advisories and releases from Http4s to stay current with the latest patches and updates addressing vulnerabilities like CVE-2023-22465.