CVE-2019-16785
HTTP Request Smuggling: LF vs CRLF handling in Waitress
- State
- Published
- Severity
- 7.1 High
- Published
- Dec 20, 2019
- Updated
- Aug 5, 2024
- Reserved
- Sep 24, 2019
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 7.1 High | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N | GitHub_M |
Weaknesses
- CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling')
Affected Products
| Product | Versions |
|---|---|
WaitressPylons |
|
References
- FEDORA-2020-bdcc8ffc24vendor-advisory
- FEDORA-2020-65a7744e38vendor-advisory
- RHSA-2020:0720vendor-advisory
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://docs.pylonsproject.org/projects/waitress/en/latest/#security-fixes
- https://github.com/Pylons/waitress/security/advisories/GHSA-pg36-wpm5-g57p
- https://github.com/Pylons/waitress/commit/8eba394ad75deaf9e5cd15b78a3d16b12e6b0eba
- [debian-lts-announce] 20220512 [SECURITY] [DLA 3000-1] waitress security updatemailing-list
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