build(deps): bump rack from 3.0.9.1 to 3.1.21 in /functions/tips/scopes

[dependabot]

Bumps rack from 3.0.9.1 to 3.1.21.

Changelog

Sourced from rack's changelog.

[3.1.21] - 2026-04-01

Security

• CVE-2026-34763 Root directory disclosure via unescaped regex interpolation in Rack::Directory.
• CVE-2026-34230 Avoid O(n^2) algorithm in Rack::Utils.select_best_encoding which could lead to denial of service.
• CVE-2026-32762 Forwarded header semicolon injection enables Host and Scheme spoofing.
• CVE-2026-26961 Raise error for multipart requests with multiple boundary parameters.
• CVE-2026-34786 Rack::Static header_rules bypass via URL-encoded path mismatch.
• CVE-2026-34831 Content-Length mismatch in Rack::Files error responses.
• CVE-2026-34826 Multipart byte range processing allows denial of service via excessive overlapping ranges.
• CVE-2026-34835 Rack::Request accepts invalid Host characters, enabling host allowlist bypass.
• CVE-2026-34830 Rack::Sendfile header-based X-Accel-Mapping regex injection enables unauthorized X-Accel-Redirect.
• CVE-2026-34785 Rack::Static prefix matching can expose unintended files under the static root.
• CVE-2026-34829 Multipart parsing without Content-Length header allows unbounded chunked file uploads.
• CVE-2026-34827 Multipart header parsing allows denial of service via escape-heavy quoted parameters.

[3.1.20] - 2026-02-16

Security

• CVE-2026-25500 XSS injection via malicious filename in Rack::Directory.
• CVE-2026-22860 Directory traversal via root prefix bypass in Rack::Directory.

[3.1.19] - 2025-11-03

Fixed

• Multipart parser: limit MIME header size check to the unread buffer region to avoid false multipart mime part header too large errors when previously read data accumulates in the scan buffer. (#2392, @​alpaca-tc, @​willnet, @​krororo)

[3.1.18] - 2025-10-10

Security

• CVE-2025-61780 Improper handling of headers in Rack::Sendfile may allow proxy bypass.
• CVE-2025-61919 Unbounded read in Rack::Request form parsing can lead to memory exhaustion.

[3.1.17] - 2025-10-07

Security

• CVE-2025-61772 Multipart parser buffers unbounded per-part headers, enabling DoS (memory exhaustion)
• CVE-2025-61771 Multipart parser buffers large non‑file fields entirely in memory, enabling DoS (memory exhaustion)
• CVE-2025-61770 Unbounded multipart preamble buffering enables DoS (memory exhaustion)

[3.1.16] - 2025-06-04

Security

• CVE-2025-49007 Fix ReDoS in multipart request.

... (truncated)

Commits

• ae84311 Bump patch version.
• 87961c3 Fix typo in test.
• fd1c23d Add logger to gemfile.
• c59d924 Fix test expectation.
• 176f468 Add Ruby v4.0 to the test matrix.
• 2856934 Drop EOL Rubies from external tests.
• 17ce783 Limit the number of quoted escapes during multipart parsing
• 367a2a0 Add Content-Length size check in Rack::Multipart::Parser
• a17cb99 Fix root prefix bug in Rack::Static
• 59a0966 Only do a simple substitution on the x-accel-mapping paths
• Additional commits viewable in compare view

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