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Product · Pylons

Waitress

9 known vulnerabilities.

Waitress at a glance

Last 12 months
0
Critical · all time
1
Exploited · all time
0
Public exploit · all time
1
New vulnerabilities per month · last 12 months
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9 results · Feed

  • Critical 9.1

    Waitress has request processing race condition in HTTP pipelining with invalid first request

    Waitress is a Web Server Gateway Interface server for Python 2 and 3. A remote client may send a request that is exactly recv_bytes (defaults to 8192) long, followed by a secondary request using HTTP pipelining. When request lookahead is disabled (default) we…

  • High 7.5

    Waitress has a denial of service leading to high CPU usage/resource exhaustion

    Waitress is a Web Server Gateway Interface server for Python 2 and 3. When a remote client closes the connection before waitress has had the opportunity to call getpeername() waitress won't correctly clean up the connection leading to the main thread attempti…

  • Medium 6.5

    Uncaught Exception (due to a data race) leads to process termination in Waitress

    Waitress is a Web Server Gateway Interface server for Python 2 and 3. Waitress versions 2.1.0 and 2.1.1 may terminate early due to a thread closing a socket while the main thread is about to call select(). This will lead to the main thread raising an exceptio…

  • High 7.5

    HTTP Request Smuggling in waitress

    Waitress is a Web Server Gateway Interface server for Python 2 and 3. When using Waitress versions 2.1.0 and prior behind a proxy that does not properly validate the incoming HTTP request matches the RFC7230 standard, Waitress and the frontend proxy may disag…

  • Medium 5.7
    CVE-2020-5236 Public exploit

    Catastrophic backtracking in regex allows Denial of Service in Waitress

    Waitress version 1.4.2 allows a DOS attack When waitress receives a header that contains invalid characters. When a header like "Bad-header: xxxxxxxxxxxxxxx\x10" is received, it will cause the regular expression engine to catastrophically backtrack causing th…

  • High 7.1

    HTTP Request Smuggling: Content-Length Sent Twice in Waitress

    Waitress through version 1.3.1 allows request smuggling by sending the Content-Length header twice. Waitress would header fold a double Content-Length header and due to being unable to cast the now comma separated value to an integer would set the Content-Len…

  • High 7.1

    HTTP Request Smuggling in Waitress: Invalid whitespace characters in headers

    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 cra…

  • High 7.1

    HTTP Request Smuggling: LF vs CRLF handling in Waitress

    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 C…

  • High 7.1

    HTTP Request Smuggling: Invalid Transfer-Encoding in Waitress

    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 sh…