- Defend against a "ReDoS"-attack form the "Content-Type" http-field.

- Call the "LoaderAndChecker.setCouldRetryRegex()" inside "UrlChecker.checkUrlConnectivity()".

src/main/java/eu/openaire/publications_retriever/util/http/ConnSupportUtils.java

@@ -358,6 +358,9 @@ public static String getPlainMimeType(String mimeType)
 		if ( mimeType == null ) {	// Null-check to avoid NPE in "matcher()".
 			logger.warn("A null mimeType was given to \"getPlainMimeType()\".");
 			return null;
+		} else if ( mimeType.length() > 200 ) {
+			logger.warn("A suspiciously large mimeType was given to \"getPlainMimeType()\", having length: " + mimeType.length());
+			return null;	// If it contains garbage, it may cause a "ReDoS"-attack, when being processed by "MIME_TYPE_FILTER"-regex.
 		}
 
 		String plainMimeType = null;

src/test/java/eu/openaire/publications_retriever/test/UrlChecker.java

@@ -792,6 +792,7 @@ public void checkUrlConnectivity()
 		// Set some needed data.
 		ConnSupportUtils.setKnownMimeTypes();
 		UrlTypeChecker.setRuntimeInitializedRegexes();
+		LoaderAndChecker.setCouldRetryRegex();
 
 		ArgsUtils.shouldDownloadDocFiles = true;
 		ArgsUtils.fileNameType = ArgsUtils.fileNameTypeEnum.idName;