TYPO3 Core

The \TYPO3\CMS\Core\Log\LogManager::getConfigurationForLogger() method accesses $GLOBALS['TYPO3_CONF_VARS']['LOG'] without checking if it really exists. Any array access should be hardened, considering PHP 8+.

It may seem unlikely that $GLOBALS['TYPO3_CONF_VARS']['LOG'] should be empty, but you never know. In my case, it happened when writing unit tests for a class which uses the LoggerAwareTrait. The Logger gets instantiated and thus tries to access the corresponding configuration, which doesn't exist when unit testing.