CVE-2023-38697

Publication date 4 August 2023

Last updated 11 July 2025

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

5.8 · Medium

Score breakdown

Description

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.

Status

Package Ubuntu Release Status
ruby-protocol-http1 26.04 LTS resolute
Needs evaluation
25.10 questing Ignored end of life, was needs-triage
25.04 plucky Ignored end of life, was needs-triage
24.10 oracular Ignored end of life, was needs-triage
24.04 LTS noble
Needs evaluation
23.10 mantic Ignored end of life, was needs-triage
23.04 lunar Ignored end of life, was needed
22.04 LTS jammy
Vulnerable
20.04 LTS focal Not in release
18.04 LTS bionic Ignored end of standard support
16.04 LTS xenial Ignored end of standard support
14.04 LTS trusty Ignored end of standard support

Severity score breakdown

CVSS version: CVSS v3.0

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

References

Other references

Access our resources on patching vulnerabilities