diff --git a/Libraries/LibCompress/GenericZlib.cpp b/Libraries/LibCompress/GenericZlib.cpp
index b8ff099744d..1ab1d992225 100644
--- a/Libraries/LibCompress/GenericZlib.cpp
+++ b/Libraries/LibCompress/GenericZlib.cpp
@@ -76,9 +76,15 @@ ErrorOr<Bytes> GenericZlibDecompressor::read_some(Bytes bytes)
     }
 
     auto ret = inflate(m_zstream, Z_NO_FLUSH);
+
     if (ret != Z_OK && ret != Z_STREAM_END && ret != Z_BUF_ERROR)
         return handle_zlib_error(ret);
 
+    // We got Z_BUF_ERROR (no progress was possible), no more input, stream is EOF and no output was produced.
+    // There is no way to get out of this loop, error out.
+    if (ret == Z_BUF_ERROR && m_zstream->avail_in == 0 && m_stream->is_eof() && bytes.size() == m_zstream->avail_out)
+        return Error::from_string_literal("No decompression progress on EOF stream");
+
     if (ret == Z_STREAM_END) {
         inflateReset(m_zstream);
         if (m_zstream->avail_in == 0)
diff --git a/Libraries/LibWeb/Compression/DecompressionStream.cpp b/Libraries/LibWeb/Compression/DecompressionStream.cpp
index 60540e4ebda..13dcf0e45b5 100644
--- a/Libraries/LibWeb/Compression/DecompressionStream.cpp
+++ b/Libraries/LibWeb/Compression/DecompressionStream.cpp
@@ -153,13 +153,13 @@ WebIDL::ExceptionOr<void> DecompressionStream::decompress_flush_and_enqueue()
         return TRY(decompressor->read_until_eof());
     });
     if (maybe_buffer.is_error())
-        return WebIDL::SimpleException { WebIDL::SimpleExceptionType::TypeError, MUST(String::formatted("Unable to compress flush: {}", maybe_buffer.error())) };
+        return WebIDL::SimpleException { WebIDL::SimpleExceptionType::TypeError, MUST(String::formatted("Unable to decompress flush: {}", maybe_buffer.error())) };
 
     auto buffer = maybe_buffer.release_value();
 
+    // Note: LibCompress already throws an error if we call read_until_eof and no more progress can be made
     // 2. If the end of the compressed input has not been reached, then throw a TypeError.
-    if (m_decompressor.visit([](auto const& decompressor) { return !decompressor->is_eof(); }))
-        return WebIDL::SimpleException { WebIDL::SimpleExceptionType::TypeError, "End of compressed input has not been reached"sv };
+    VERIFY(m_decompressor.visit([](auto const& decompressor) { return decompressor->is_eof(); }));
 
     // 3. If buffer is empty, return.
     if (buffer.is_empty())