TYPO3 Core

In TYPO3 v12.4.28 with PHP 8.4, a critical error occurs in LocalizationUtility.php when accessing the "Usuarios de backend" module with the backend language set to Spanish. The issue seems to be caused by an invalid format specifier in a translation string.

Log output:

[CRITICAL] request="422d3a6447131" component="TYPO3.CMS.Core.Error.ProductionExceptionHandler": Core: Exception handler (WEB: BE): ValueError, code #0, file /var/www/cms_typo3/vendor/typo3/cms-extbase/Classes/Utility/LocalizationUtility.php, line 91: Unknown format specifier "?"

Steps to reproduce

Set the TYPO3 backend language to Spanish.
Go to TYPO3 Backend > Usuarios de backend.
TYPO3 crashes with a ValueError: Unknown format specifier "?".

Expected behavior

Instead of throwing a critical error, the system should handle incorrect placeholders gracefully.
Suggested Fix

Modify LocalizationUtility.php (lines 87-93) to validate placeholders before calling sprintf().

Current code:

if (is_array($arguments) && $arguments !== [] && $value !== null) {
return sprintf($value, ...array_values($arguments)) ?: sprintf(
'Error: could not translate key "%s" with value "%s" and %d argument(s)!',
$key,
$value,
count($arguments)
);
}

Proposed fix:

if (is_array($arguments) && $arguments !== [] && strpos($value, '%') !== false) {
preg_match_all('/%[a-zA-Z]/', $value, $matches);
if (count($matches⁰) !== count($arguments)) {
return sprintf('Error: could not translate key "%s" with value "%s" and %d argument(s)!', $key, $value, count($arguments));
}
}