Vulnerability in Socketry Protocol-Http1
CVE-2023-38697
protocol-http1 provides a low-level implementation of the HTTP/1 protocol. RFC 9112 Section 7.1 defined the format of chunk size, chunk data and chunk extension. 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, and the chunk extension shouldn't contain any invisible character. However, Falcon has following behaviors while disobey the corresponding RFCs: accepting Content-Length header values that have `+` prefix, accepting Content-Length header values that written in hexadecimal with `0x` prefix, accepting `0x` and `+` prefixed chunk size, and accepting 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. This issue is fixed in `protocol-http1` v0.15.1. There are no known workarounds.
Vulnerability class: HTTP Request Smuggling
EPSS: 0.006 (46.9th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.8 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N.
Affected products
- Socketry Protocol-http1 — versions < 0.15.1
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)
- security-advisories@github.com (x_refsource_MISC, Issue Tracking)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Technical Description, x_refsource_MISC)
Frequently asked questions
- What is CVE-2023-38697?
- CVE-2023-38697 is a medium-severity vulnerability in Socketry Protocol-Http1, classified under Inconsistent Interpretation of HTTP Requests (HTTP Request/Response Smuggling). CVSS score: 5.8/10. Published 2023-08-04.
- How severe is CVE-2023-38697?
- Medium severity. CVSS v3 base score is 5.8 out of 10.