CVE-2020-26281

Published Dec 21, 2020

Last updated 4 years ago

Overview

Description
async-h1 is an asynchronous HTTP/1.1 parser for Rust (crates.io). There is a request smuggling vulnerability in async-h1 before version 2.3.0. This vulnerability affects any webserver that uses async-h1 behind a reverse proxy, including all such Tide applications. If the server does not read the body of a request which is longer than some buffer length, async-h1 will attempt to read a subsequent request from the body content starting at that offset into the body. One way to exploit this vulnerability would be for an adversary to craft a request such that the body contains a request that would not be noticed by a reverse proxy, allowing it to forge forwarded/x-forwarded headers. If an application trusted the authenticity of these headers, it could be misled by the smuggled request. Another potential concern with this vulnerability is that if a reverse proxy is sending multiple http clients' requests along the same keep-alive connection, it would be possible for the smuggled request to specify a long content and capture another user's request in its body. This content could be captured in a post request to an endpoint that allows the content to be subsequently retrieved by the adversary. This has been addressed in async-h1 2.3.0 and previous versions have been yanked.
Source
security-advisories@github.com
NVD status
Analyzed

Risk scores

CVSS 3.1

Type
Primary
Base score
7.5
Impact score
4.7
Exploitability score
2.2
Vector string
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:H/A:N
Severity
HIGH

CVSS 2.0

Type
Primary
Base score
5.8
Impact score
4.9
Exploitability score
8.6
Vector string
AV:N/AC:M/Au:N/C:P/I:P/A:N

Weaknesses

security-advisories@github.com
CWE-444

Social media

Hype score
Not currently trending

Configurations