CVE-2020-5236

Published Feb 4, 2020

Last updated 5 years ago

Overview

Description
Waitress version 1.4.2 allows a DOS attack When waitress receives a header that contains invalid characters. When a header like "Bad-header: xxxxxxxxxxxxxxx\x10" is received, it will cause the regular expression engine to catastrophically backtrack causing the process to use 100% CPU time and blocking any other interactions. This allows an attacker to send a single request with an invalid header and take the service offline. This issue was introduced in version 1.4.2 when the regular expression was updated to attempt to match the behaviour required by errata associated with RFC7230. The regular expression that is used to validate incoming headers has been updated in version 1.4.3, it is recommended that people upgrade to the new version of Waitress as soon as possible.
Source
security-advisories@github.com
NVD status
Analyzed

Social media

Hype score
Not currently trending

Risk scores

CVSS 3.1

Type
Primary
Base score
6.5
Impact score
3.6
Exploitability score
2.8
Vector string
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

CVSS 2.0

Type
Primary
Base score
6.8
Impact score
6.9
Exploitability score
8
Vector string
AV:N/AC:L/Au:S/C:N/I:N/A:C

Weaknesses

nvd@nist.gov
CWE-400
security-advisories@github.com
CWE-400

Configurations