CVE-2019-16785

 

Published at: - 21-12-2019 12:15

Last modified: - 23-09-2022 08:58

Total changes: - 4

Description

Waitress through version 1.3.1 implemented a "MAY" part of the RFC7230 which states: "Although the line terminator for the start-line and header fields is the sequence CRLF, a recipient MAY recognize a single LF as a line terminator and ignore any preceding CR." Unfortunately if a front-end server does not parse header fields with an LF the same way as it does those with a CRLF it can lead to the front-end and the back-end server parsing the same HTTP message in two different ways. This can lead to a potential for HTTP request smuggling/splitting whereby Waitress may see two requests while the front-end server only sees a single HTTP message. This issue is fixed in Waitress 1.4.0.

Common Vulnerability Scoring System (CVSS)

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

 

Verification logic

 

Reference

• https://github.com/Pylons/waitress/security/advisories/GHSA-pg36-wpm5-g57p
• https://github.com/Pylons/waitress/commit/8eba394ad75deaf9e5cd15b78a3d16b12e6b0eba
• https://docs.pylonsproject.org/projects/waitress/en/latest/#security-fixes
• FEDORA-2020-bdcc8ffc24-Mailing List, Third Party Advisory
• FEDORA-2020-65a7744e38-Mailing List, Third Party Advisory
• RHSA-2020:0720-Third Party Advisory
• https://www.oracle.com/security-alerts/cpuapr2022.html
• [debian-lts-announce] 20220512 [SECURITY] [DLA 3000-1] waitress security update-Mailing List, Third Party Advisory

 

Keywords

NVD

 

CVE-2019-16785

 

CVE

 

Common vulnerabilities & exposures

 

CVSS

 

Common vulnerability scoring system

 

Security

 

Vulnerabilities

 

Exposures