Vulnerability in Agendaless Waitress
CVE-2019-16785
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.
Vulnerability class: HTTP Request Smuggling
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N.
EPSS exploit prediction
EPSS: 0.025 (84.3th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 84th percentile — 84.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.025 · newest: 0.025 · change: 0.000
Affected products
- Agendaless Waitress
- Oracle Communications Cloud Native Core Network Function Environment — versions 1.10.0
- Pylons Waitress — versions <= 1.3.1
- Debian Linux — versions 9.0
- Fedoraproject Fedora — versions 30, 31
- Red Hat OpenStack — versions 15
Weakness classification (CWE)
Public proof-of-concept exploits
References
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- access.redhat.com/errata/RHSA-2020:0720 (vendor-advisory, Third Party Advisory)
- www.oracle.com/security-alerts/cpuapr2022.html (Patch, Third Party Advisory)
- docs.pylonsproject.org/projects/waitress/en/latest/ (Vendor Advisory)
- github.com/Pylons/waitress/security/advisories/GHSA-pg36-wpm5-g57p (Exploit, Third Party Advisory)
- github.com/Pylons/waitress/commit/8eba394ad75deaf9e5cd15b78a3d16b12e6b0eba (Patch, Third Party Advisory)
- lists.debian.org/debian-lts-announce/2022/05/msg00011.html (mailing-list, Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2019-16785?
- CVE-2019-16785 is a high-severity vulnerability in Agendaless Waitress, classified under Inconsistent Interpretation of HTTP Requests (HTTP Request/Response Smuggling). CVSS score: 7.1/10. Published 2019-12-20.
- How severe is CVE-2019-16785?
- High severity. CVSS v3 base score is 7.1 out of 10.
- Is CVE-2019-16785 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.