[Mailer][Notifier] Harden Mailchimp signature comparison and Smsbox IP allowlist#64344
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nicolas-grekas merged 1 commit intoMay 23, 2026
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[Mailer][Notifier] Harden Mailchimp signature comparison and Smsbox IP allowlist#64344nicolas-grekas merged 1 commit intosymfony:7.4symfony/symfony:7.4from nicolas-grekas:harden-mailchimp-smsbox-webhook-7.4nicolas-grekas/symfony:harden-mailchimp-smsbox-webhook-7.4Copy head branch name to clipboard
nicolas-grekas merged 1 commit into
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…P allowlist * Mailchimp: use `hash_equals` instead of `!==` for the HMAC-SHA1 signature comparison (timing-safe) * Smsbox: expose `PROVIDER_IPS` as a public const and add an `$allowedIPs` constructor argument so the hardcoded SMSBox IP list can be overridden without subclassing
This was referenced May 27, 2026
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Two small hardenings spotted while reviewing the webhook parsers.
MailchimpRequestParser::validateSignature()compared the HMAC with!==, the only parser in the cluster doing the comparison non-constant-time. Swapped forhash_equals()to remove the timing side-channel. Both branches reject the same inputs, so no functional change.SmsboxRequestParser::getRequestMatcher()hardcoded the six provider IPs inside the method body with no override path. Added aPROVIDER_IPSpublic const and an$allowedIPsconstructor argument so operators can extend or replace the list without subclassing, mirroring the shape already used for Postmark. The default behavior is unchanged.