Sourced from path-to-regexp's releases.

v8.4.2

Fixed

• Error on trailing backslash (#434) 9a78879

Performance

• Minimize array allocations (#437) 937c02d
• Improve compile performance (#436) 57247e6
  • Should improve compilation performance by ~25%
• Remove internal tokenization during parse (#435) 5844988
  • Should improve parse performance by ~20%

Bundle size to 1.93 kB, from 1.97 kB.

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https://github.com/pillarjs/path-to-regexp/compare/v8.4.1...v8.4.2

v8.4.1

Fixed

• Remove trie deduplication (#431) 6bc8e84
  • Using a trie required non-greedy matching, which regressed wildcards in non-ending mode by matching them up until the first match. For example:
    • /*foo with /a/b = /a
    • /*foo.htmlwith /a/b.html/c.html = /a/b.html
• Allow backtrack handling to match itself (#427) 5bcd30b
  • When backtracking was introduced, it rejected matching things like /:"a"_:"b" against /foo__. This makes intuitive sense because the second parameter is not going to backtrack on _ anymore, but it's somewhat unexpected since there's no reason it shouldn't match the second _.

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https://github.com/pillarjs/path-to-regexp/compare/v8.4.0...v8.4.1

v8.4.0

Important

• Fix CVE-2026-4926 (GHSA-j3q9-mxjg-w52f)
• Fix CVE-2026-4923 (GHSA-27v5-c462-wpq7)

Fixed

• Restricts wildcard backtracking when using more than 1 in a path (pillarjs/path-to-regexp#421)

Changed

• Dedupes regex prefixes (pillarjs/path-to-regexp#422)
  • This will result in shorter regular expressions for some cases using optional groups
• Rejects large optional route combinations (pillarjs/path-to-regexp#424)
  • When using groups such as /users{/delete} it will restrict the number of generated combinations to < 256, equivalent to 8 top-level optional groups and unlikely to occur in a real world application, but avoids exploding the regex size for applications that accept user created routes

• cbf3025 8.4.2
• 937c02d Minimize array allocations (#437)
• 57247e6 Improve compile performance (#436)
• 5844988 Remove internal tokenization during parse (#435)
• 9a78879 Error on trailing backslash (#434)
• 7f05876 8.4.1
• 6bc8e84 Remove trie deduplication (#431)
• 5bcd30b Allow backtrack handling to match itself (#427)
• 9f9c6c5 Add parsing to benchmarks (#418)
• 9fd31e0 Add trailing: false tests (#428)
• Additional commits viewable in compare view