#63949: Keep SNI enabled when SSL verification is disabled

[ArkaPrabhaChowdhury]

The PHP streams (fsockopen) transport disables Server Name Indication (SNI) whenever verifyname is false. WP-Cron's loopback request defaults to sslverify => false, which WordPress maps to verifyname => false. On a virtual host that requires SNI, that combination can send the request to the default TLS host and produce an HTTP 421 response.

Keep SNI enabled when the PHP/OpenSSL runtime supports it. Certificate verification remains disabled as requested; SNI still supplies the URL hostname during the TLS handshake. This is the same change already accepted on the Requests develop branch: WordPress/Requests@213f7e7. It also addresses the mechanism described in https://core.trac.wordpress.org/ticket/50288.

A local TLS listener recorded the SNI sent by Requests with verify => false and verifyname => false:

Transport	SNI before	SNI with patch
cURL	localhost	unchanged
fsockopen	absent	localhost

Both transports received HTTP 200 from the local listener. This verifies the SNI behavior; the reporter's Apache environment and active transport are not available, so the reported 421 response has not been reproduced end to end.

Checks: PHPCBF, PHPCS, PHP syntax, and git diff --check passed. Core PHPUnit was not run locally because this worktree has no wp-tests-config.php.

Trac ticket: https://core.trac.wordpress.org/ticket/63949

Use of AI Tools

AI assistance: Yes
Tool(s): OpenAI Codex
Model(s): GPT-6
Used for: Ticket investigation, implementation, local SNI probe, and validation. The change and evidence were reviewed before publication.

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