Vulnerability in Agendaless Waitress
CVE-2019-16789
In Waitress through version 1.4.0, if a proxy server is used in front of waitress, an invalid request may be sent by an attacker that bypasses the front-end and is parsed differently by waitress leading to a potential for HTTP request smuggling. Specially crafted requests containing special whitespace characters in the Transfer-Encoding header would get parsed by Waitress as being a chunked request, but a front-end server would use the Content-Length instead as the Transfer-Encoding header is considered invalid due to containing invalid characters. If a front-end server does HTTP pipelining to a backend Waitress server this could lead to HTTP request splitting which may lead to potential cache poisoning or unexpected information disclosure. This issue is fixed in Waitress 1.4.1 through more strict HTTP field validation.
Vulnerability class: HTTP Request Smuggling
EPSS: 0.026 (83.7th percentile) — read the EPSS interpretation.
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:L/I:H/A:N.
Affected products
- Agendaless Waitress
- Oracle Communications_cloud_native_core_network_function_cloud_native_environment — versions 1.10.0
- Pylons Waitress — versions < 1.4.1
- Debian Debian_linux — versions 9.0
- Fedoraproject Fedora — versions 30, 31
- Redhat Openstack — versions 15
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security-advisories@github.com (x_refsource_FEDORA, vendor-advisory)
- security-advisories@github.com (x_refsource_FEDORA, vendor-advisory)
- security-advisories@github.com (x_refsource_REDHAT, vendor-advisory, Third Party Advisory)
- security-advisories@github.com (Patch, Third Party Advisory, x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC, Release Notes, Vendor Advisory)
- security-advisories@github.com (x_refsource_CONFIRM, Third Party Advisory, Broken Link)
- security-advisories@github.com (Patch, Third Party Advisory, x_refsource_MISC)
- security-advisories@github.com (mailing-list, x_refsource_MLIST, Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2019-16789?
- CVE-2019-16789 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 2019-12-26.
- How severe is CVE-2019-16789?
- High severity. CVSS v3 base score is 7.1 out of 10.
- Is CVE-2019-16789 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.