TYPO3 Core

If you have the PHP Extension XML in use, the Extension Import is done by ExtensionXmlPushParser

This sets the xml_set_character_data_handler for reading the data between the tags, but this function can be called multiple times per tag. The yet existing implementation can lead to missing/incorrect data (maybe dependency string can't be unserialized, as it happens on my sytsem for bootstrap_package 8.0.0 at the moment).

Found this issue in 7 LTS maybe it is older.

From function documentation: http://php.net/xml_set_character_data_handler
"Character data handler is called for every piece of a text in the XML document. It can be called multiple times inside each fragment (e.g. for non-ASCII strings)."