Medium, CVSS 5.8RubyGemsPublished
protocol-http1 HTTP Request/Response Smuggling vulnerability
CVE-2023-38697 · GHSA-6jwc-qr2q-7xwj
- Affected
- RubyGems protocol-http1 < 0.15.1
- Fixed in
- 0.15.1· Vendor fix available
- Issue
- Impact RFC 9112 Section 7.1 defined the format of chunk size, chunk data and chunk extension (detailed ABNF is in Appendix section). In summary: - The value of Content-Length header should be a string of 0-9 digits. - The chunk size should be a string of hex digits and should split from chunk data using CRLF. - The chunk extension shouldn't contain any invisible character. However, we found that Falcon has following behaviors while disobey the corresponding RFCs. - Falcon accepts Content-Length header values that have "+" prefix. - Falcon accepts Content-Length header values that written in hexadecimal with "0x" prefix. - Falcon accepts "0x" and "+" prefixed chunk size. - Falcon accepts LF in chunk extension. This behavior can lead to desync when forwarding through multiple HTTP parsers, potentially results in HTTP request smuggling and firewall bypassing. Note that while these issues were reproduced in Falcon (the server), the issue is with protocol-http1 which implements the HTTP/1…
Recommended action: Upgrade to 0.15.1 or later, then redeploy and verify.A vendor fix does not resolve your finding until you verify it in your own systems.