TYPO3 Core

I don't know why but this bug seems to be a feature...

There is a check that the referer is equal to the site before doing a redirect. You may deactivate this check by commenting this line in file typo3/sysext/cms/tslib/index_ts.php

// ************************
// Check JumpUrl
// ***********************
$TSFE->setExternalJumpUrl();
#$TSFE->checkJumpUrlReferer(); <--- comment this line

Unless there is a good reason to leave this check (please explain!), could it be removed from the code?

Worked fine for me, thanks.

Considering this is a Feature, the checkJumpUrlReferer method should case insensitive compare hostnames:
Referer can include Uppercase hostnames e.g. in Safari! This leads to not redirecting the user even he is "on" the site, but with uppercased hostname parts like WWW.This-Is-My-T3-Website.com.

Therefor you should include this patch:
diff ruw typo3_src-4.4.4.orig typo3_src-4.4.4
diff -ruw typo3_src-4.4.4.orig/typo3/sysext/cms/tslib/class.tslib_fe.php typo3_src-4.4.4/typo3/sysext/cms/tslib/class.tslib_fe.php
-- typo3_src-4.4.4.orig/typo3/sysext/cms/tslib/class.tslib_fe.php 2010-10-06 10:40:06.000000000 0200
++ typo3_src-4.4.4/typo3/sysext/cms/tslib/class.tslib_fe.php 2010-11-19 11:06:36.000000000 0100
@ -2619,7 +2619,7 @
function checkJumpUrlReferer() {
if (strlen($this->jumpurl) && !$this->TYPO3_CONF_VARS['SYS']['doNotCheckReferer']) {
$referer = parse_url(t3lib_div::getIndpEnv('HTTP_REFERER'));
- if (isset($referer['host']) && !($referer['host'] == t3lib_div::getIndpEnv('TYPO3_HOST_ONLY'))) {
if (isset($referer['host']) && (strcasecmp($referer['host'], t3lib_div::getIndpEnv('TYPO3_HOST_ONLY')) != 0)) {
unset($this->jumpurl);
}
}

The same problem exists if you try to switch two domains within TYPO3 with the language selector and you have links to external urls set as an alternative language inside a page:

same her in TYPO3 6.1.6

and in 6.1.7
When page type is 'external url' and page is in menu, then the redirect to the external url does not work. Only after second click and when cached? it works...

I have the same problem in TYPO3 6.2.4. I have a multi site installation and I included some footer links of type external url from another domain. The links rendered absolute but the redirect not working. The referer check forbidden this. I deactivate ther referrer check in the localconfiguration

[SYS][doNotCheckReferer] = 1

But I'm not shure, if this is problematic for security or other reasons.