[Security] Bump waitress from 0.8.10 to 1.4.1

[dependabot-preview]

Bumps waitress from 0.8.10 to 1.4.1. This update includes security fixes.

Vulnerabilities fixed

Sourced from The GitHub Security Advisory Database.

High severity vulnerability that affects waitress

Impact

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.

Content-Length: 10
Transfer-Encoding: [\x0b]chunked

For clarity:

0x0b == vertical tab

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.

Patches

... (truncated)

Affected versions: < 1.4.1

Sourced from The GitHub Security Advisory Database.

Critical severity vulnerability that affects waitress

Impact

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-Length to 0 internally.

So a request with:

Content-Length: 10
Content-Length: 10

would get transformed to:

Content-Length: 10, 10

Which would Waitress would then internally set to Content-Lenght: 0.

Waitress would then treat the request as having no body, thereby treating the body of the request as a new request in HTTP pipelining.

... (truncated)

Affected versions: < 1.3.1

Sourced from The GitHub Security Advisory Database.

Critical severity vulnerability that affects waitress

Impact

Waitress implemented a "MAY" part of the RFC7230 (https://tools.ietf.org/html/rfc7230#section-3.5) 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.

Example:

Content-Length: 100[CRLF]
X-Header: x[LF]Content-Length: 0[CRLF]

Would get treated by Waitress as if it were:

</tr></table> ... (truncated)
Affected versions: <= 1.3.1

Sourced from The GitHub Security Advisory Database.

Critical severity vulnerability that affects waitress

Impact

Waitress 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.

Patches

This issue is fixed in Waitress 1.4.0. This brings a range of changes to harden Waitress against potential HTTP request confusions, and may change the behaviour of Waitress behind non-conformist proxies.

... (truncated)

Affected versions: <= 1.3.1

Release notes

Sourced from waitress's releases.

v1.4.1

No release notes provided.

v1.4.0

No release notes provided.

v1.3.1

No release notes provided.

v1.3.0

No release notes provided.

v1.3.0b0

No release notes provided.

v1.2.1

No release notes provided.

v1.2.0

No release notes provided.

v1.1.0

https://pypi.org/project/waitress/1.1.0/

v1.0.2

No release notes provided.

v1.0.1

No release notes provided.

v1.0.0

No release notes provided.

v1.0a2

No release notes provided.

v1.0a1

No release notes provided.

v0.9.0

No release notes provided.

v0.9.0b1

No release notes provided.

0.9.0b0

No release notes provided.

0.8.11b0

No release notes provided.

... (truncated)

Changelog

Sourced from waitress's changelog.

1.4.1 (2019-12-24)

Security Fixes

- Waitress did not properly validate that the HTTP headers it received were
  properly formed, thereby potentially allowing a front-end server to treat a
  request different from Waitress. This could lead to HTTP request
  smuggling/splitting.
Please see the security advisory for more information:
https://github.com/Pylons/waitress/security/advisories/GHSA-m5ff-3wj3-8ph4
1.4.0 (2019-12-20)
Bugfixes

- Waitress used to slam the door shut on HTTP pipelined requests without
  setting the ``Connection: close`` header as appropriate in the response. This
  is of course not very friendly. Waitress now explicitly sets the header when
  responding with an internally generated error such as 400 Bad Request or 500
  Internal Server Error to notify the remote client that it will be closing the
  connection after the response is sent.

Waitress no longer allows any spaces to exist between the header field-name

and the colon. While waitress did not strip the space and thereby was not

vulnerable to any potential header field-name confusion, it should have sent

back a 400 Bad Request. See https://github.com/Pylons/waitress/issues/273

Security Fixes

</code></pre>

<ul>

<li>

<p>Waitress implemented a &quot;MAY&quot; part of the RFC7230

(<a href="https://tools.ietf.org/html/rfc7230#section-3.5&quot;&gt;https://tools.ietf.org/html/rfc7230#section-3.5&lt;/a>) which states:</p>

<pre><code>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.

</code></pre>

<p>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.</p>

<p>For more information I can highly recommend the blog post by ZeddYu Lu</p>

</li>

</ul>

</tr></table> ... (truncated)

</blockquote>

</details>

<details>

<summary>Commits</summary>
<ul>

<li><a href="https://github.com/Pylons/waitress/commit/cd8359864400592ba0db5d74e650a8fac4763d0d&quot;&gt;&lt;code&gt;cd83598&lt;/code&gt;&lt;/a> Prep v1.4.1</li>

<li><a href="https://github.com/Pylons/waitress/commit/11d9e138125ad46e951027184b13242a3c1de017&quot;&gt;&lt;code&gt;11d9e13&lt;/code&gt;&lt;/a> Merge pull request from GHSA-m5ff-3wj3-8ph4</li>

<li><a href="https://github.com/Pylons/waitress/commit/a046a7667c8a7afa0237c668e6ff33f7c10894f7&quot;&gt;&lt;code&gt;a046a76&lt;/code&gt;&lt;/a> Add links to advisories for previous security issues</li>

<li><a href="https://github.com/Pylons/waitress/commit/3c58e397cc17e51e1127e971621fb617b04bd33d&quot;&gt;&lt;code&gt;3c58e39&lt;/code&gt;&lt;/a> Bump version number</li>

<li><a href="https://github.com/Pylons/waitress/commit/de3324dd2126ce7ae1e55411f2684c333d96d62b&quot;&gt;&lt;code&gt;de3324d&lt;/code&gt;&lt;/a> Add documentation for security issue</li>

<li><a href="https://github.com/Pylons/waitress/commit/3bcd690f3a068e63faae898f255df047e1ae884c&quot;&gt;&lt;code&gt;3bcd690&lt;/code&gt;&lt;/a> Define VCHAR/OBS_TEXT once</li>

<li><a href="https://github.com/Pylons/waitress/commit/2e46f2426e2845e6a088e21451d3d0031b804cea&quot;&gt;&lt;code&gt;2e46f24&lt;/code&gt;&lt;/a> Validate HTTP header-field more completely</li>

<li><a href="https://github.com/Pylons/waitress/commit/2a11d6812f703e01150c2aedbca7ec2a6590f254&quot;&gt;&lt;code&gt;2a11d68&lt;/code&gt;&lt;/a> Add file with RFC7230 definitions/ABNF -&gt; regex</li>

<li><a href="https://github.com/Pylons/waitress/commit/f11093a6b3240fc26830b6111e826128af7771c3&quot;&gt;&lt;code&gt;f11093a&lt;/code&gt;&lt;/a> Merge pull request from GHSA-g2xc-35jw-c63p</li>

<li><a href="https://github.com/Pylons/waitress/commit/e586be8f43dbb266b9ef28bb285408b3ac3dacd4&quot;&gt;&lt;code&gt;e586be8&lt;/code&gt;&lt;/a> Version 1.4.0</li>

<li>Additional commits viewable in <a href="https://github.com/Pylons/waitress/compare/0.8.10...v1.4.1&quot;&gt;compare view</a></li>

</ul>

</details>
<br />



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