Fix ReDoS in Bootstrap sample

[wukunyu264]

{PR title}

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Description

{Detail}

Fixes #{63264}
The Bootstrap JS vendored by the sample contains three uses of:
/.*(?=#[^\s]+$)/
src/Security/samples/ClaimsTransformation/wwwroot/lib/bootstrap/dist/js/bootstrap.js（513，707，1267）
to keep the trailing #… part of a URL. This pattern can catastrophically backtrack under crafted inputs and cause high CPU.
Changes (two lines only)

line 514：

- href = href.replace(/.*(?=#[^\s]+$)/, '') // strip for ie7
+ href = href && href.indexOf('#') !== -1 ? href.slice(href.lastIndexOf('#')) : href // strip for ie7 (safe)

line 708：

- || (href = $trigger.attr('href')) && href.replace(/.*(?=#[^\s]+$)/, '') // strip for ie7
+ || ((href = $trigger.attr('href')) && (href.indexOf('#') !== -1 ? href.slice(href.lastIndexOf('#')) : href)) // strip for ie7 (safe)

line 1268：

- (href && href.replace(/.*(?=#[^\s]+$)/, '')) // strip for ie7
+ (href && href.replace(/^[^#]*(?=#\S+$)/, '')) // strip for ie7 - safe

Why

/.(?=#[^\s]+$)/ mixes a greedy . with an end-anchored look-ahead; inputs like very long runs of characters followed by a short terminator can trigger catastrophic backtracking (ReDoS).

The replacement using href.slice(href.lastIndexOf('#')) preserves exactly the same behavior (keep the trailing #… segment when present) with linear complexity and no new dependencies.

Tests

How to run:

git clone https://github.com/wukunyu264/aspnetcore.git
cd src/Security/samples/ClaimsTransformation/wwwroot/lib/bootstrap
node --test 

before：

after：

gist：https://gist.github.com/wukunyu264/05afd852d727cbc6d4ab533e363fd886
https://gist.github.com/wukunyu264/d6465afd5e9f30356a200e78110920cf
https://gist.github.com/wukunyu264/932fea8d20d9e4c5059fd119e4f463c0

[dotnet-policy-service]

Thanks for your PR, @@wukunyu264. Someone from the team will get assigned to your PR shortly and we'll get it reviewed.

[wukunyu264]

@dotnet-policy-service agree

[wukunyu264]

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[dotnet-policy-service]

Looks like this PR hasn't been active for some time and the codebase could have been changed in the meantime.
To make sure no conflicting changes have occurred, please rerun validation before merging. You can do this by leaving an /azp run comment here (requires commit rights), or by simply closing and reopening.

[wukunyu264]

Hi team - I have updated this PR: I have fixed another Redos vulnerability in the same file, resolved the conflict based on the latest main content, and included previous feedback. I also ran CI again to clear outdated status (/azp run).
The test passed locally; If you need anything else, please let me know. Thank you!