diff --git a/Userland/Libraries/LibPDF/Parser.cpp b/Userland/Libraries/LibPDF/Parser.cpp
index 59682cf8f6..95f9c8dea6 100644
--- a/Userland/Libraries/LibPDF/Parser.cpp
+++ b/Userland/Libraries/LibPDF/Parser.cpp
@@ -282,6 +282,9 @@ PDFErrorOr<DeprecatedString> Parser::parse_literal_string()
     auto opened_parens = 0;
 
     while (true) {
+        if (m_reader.done())
+            return error("unterminated string literal");
+
         if (m_reader.matches('(')) {
             opened_parens++;
             builder.append(m_reader.consume());