Use wp_rand() for security-sensitive token generation

[tanjiroK-coder]

Replace remaining uses of PHP's legacy rand() and mt_rand() functions with WordPress's wp_rand() when generating security-relevant tokens.

Changes

wp-admin/includes/file.php

Replace:

$scrape_key   = md5( rand() );
$scrape_nonce = (string) rand();

with:

$scrape_key   = md5( wp_rand() );
$scrape_nonce = (string) wp_rand();

These values are used by the plugin/theme file editor's fatal-error scraping workflow and represent short-lived authorization tokens.

wp-includes/ms-functions.php

Replace:

$hash = md5( $value . time() . mt_rand() );

with:

$hash = md5( $value . time() . wp_rand() );

The generated hash is used as the confirmation token during multisite network administrator email change requests.

Rationale

WordPress core generally uses wp_rand() for generating security-sensitive values. wp_rand() is backed by a cryptographically secure random source where available, whereas rand() and mt_rand() are not intended for security-sensitive use cases.

This change improves consistency across core and ensures that all token-generation paths rely on the same secure randomness mechanism.

[github-actions]

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[github-actions]

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