CVE-2019-16786

Description

Waitress through version 1.3.1 would parse the Transfer-Encoding header and only look for a single string value, if that value was not chunked it would fall through and use the Content-Length header instead. According to the HTTP standard Transfer-Encoding should be a comma separated list, with the inner-most encoding first, followed by any further transfer codings, ending with chunked. Requests sent with: "Transfer-Encoding: gzip, chunked" would incorrectly get ignored, and the request would use a Content-Length header instead to determine the body size of the HTTP message. This could allow for Waitress to treat a single request as multiple requests in the case of HTTP pipelining. This issue is fixed in Waitress 1.4.0.

Risk Information

Base Score

7.5

MODERATE

Vector

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

EPSS Score

Exploitation Probability

0.898

Associated Vulnerability

Vulnerability	OS Platform
Vulnerabilities CVE-2019-16785,CVE-2019-16786,CVE-2019-16792 are fixed in Python-waitress 1.4.0	Windows
Vulnerabilities CVE-2019-16785,CVE-2019-16786,CVE-2019-16792 are fixed in Python-waitress for linux 1.4.0	Linux

Patch Details

No records found

References

https://nvd.nist.gov/vuln/detail/CVE-2023-1234
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-1234