CVE-2022-41721: golang h2c HTTP Request/Response Smuggling

Vulnerability summary

CVE-2022-41721 is a high (CVSS 7.5) HTTP Request/Response Smuggling vulnerability in golang h2c. EPSS estimates a 1.81% chance of exploitation in the next 30 days, higher than 78.3% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 13-01-2023
   PublishedVulnerability first disclosed.
2. 04-04-2025
   Last modifiedVulnerability information updated.

Description

A request smuggling attack is possible when using MaxBytesHandler. When using MaxBytesHandler, the body of an HTTP request is not fully consumed. When the server attempts to read HTTP2 frames from the connection, it will instead be reading the body of the HTTP request, which could be attacker-manipulated to represent arbitrary HTTP2 requests.

• CWE-444Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.