[Security] Bump rack from 1.6.4 to 1.6.11

[dependabot-preview]

Bumps rack from 1.6.4 to 1.6.11. This update includes security fixes.

Vulnerabilities fixed

Sourced from The Ruby Advisory Database.

Possible XSS vulnerability in Rack
There is a possible XSS vulnerability in Rack. Carefully crafted requests can impact the data returned by the scheme method on Rack::Request. Applications that expect the scheme to be limited to "http" or "https" and do not escape the return value could be vulnerable to an XSS attack.

Vulnerable code looks something like this:

<%= request.scheme.html_safe %>

Note that applications using the normal escaping mechanisms provided by Rails may not impacted, but applications that bypass the escaping mechanisms, or do not use them may be vulnerable.

All users running an affected release should either upgrade or use one of the workarounds immediately.

Patched versions: ~> 1.6.11; >= 2.0.6
Unaffected versions: none

Commits

• 2bef132 Bumping version for release
• 97ca63d Whitelist http/https schemes
• 7b5054e Merge pull request #1296 from tomelm/fix-prefers-plaintext
• fdcd03a Bump version for release
• 2293c6a Merge pull request #1249 from mclark/handle-invalid-method-parameters
• b27dd86 handle failure to upcase invalid strings
• 274d934 Stick with a passing version of Rubygems and bundler
• 617aac0 bump version for release
• dc017e7 Merge pull request #1237 from eileencodes/backport-1137
• 4d6965a Backport pull request #1137 from unabridged/fix-eof-failure
• Additional commits viewable in compare view

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