{"version":"2.1.251","anchor":"custom-headers-from-settings-are-now-validated-before-reachi","canonical_anchor":"custom-headers-from-settings-are-now-validated-before-reachi","heading":"Custom headers from settings are now validated before reaching the environment","tier":"notice","area":"Settings","scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.251\/e\/custom-headers-from-settings-are-now-validated-before-reachi","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.251","markdown":"### Custom headers from settings are now validated before reaching the environment\n\nCustom headers from settings are validated before entering the environment.\n\n**What**\n\nA `ANTHROPIC_CUSTOM_HEADERS` value supplied through settings used to be copied into the process environment unchecked. It now has to pass a validation step first, closing a path where settings could inject arbitrary header material.\n\n**Details**\n\n- Rejects bare carriage-return line endings and any header line whose value looks like a redirect payload.\n- Rejects header names matching a broad sensitive-key pattern covering auth, key, token, cookie, secret, credential, session, signature, passw and jwt.\n- Always enforced; this removes a previous bypass rather than adding an opt-in.\n\n**Evidence**\n\n`ANTHROPIC_CUSTOM_HEADERS`\n\n- Area: Settings\n- Names: `ANTHROPIC_CUSTOM_HEADERS`\n- Tier: You'll notice\n- Useful: 3\/5\n- Signal: 3\/5"}