Download [https://dctf.dragonsec.si/files/965ff2b168f6cee4e065c84584a8da2d/nyan.pdf?token=eyJ1c2VyX2lkIjo2MDEsInRlYW1faWQiOjQ4OSwiZmlsZV9pZCI6MTkzfQ.YKNNDw.yilClSMhmFogAyblig04siTc1bI](http://)

hint in the title Show us your ID<-----------hint

strings nyan.pdf | grep ID=

" id="646374667b3362306261347d"?> <x:xmpmeta xmlns:x="adobe:ns:meta/" x:xmptk="Adobe XMP Core 5.6-c111 79.158325, 2015/09/10-01:10:20 "> <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"> <rdf:Description rdf:about="" xmlns:xmpMM="http://ns.adobe.com/xap/1.0/mm/" xmlns:stEvt="http://ns.adobe.com/xap/1.0/sType/ResourceEvent#" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:photoshop="http://ns.adobe.com/photoshop/1.0/" xmlns:xmp="http://ns.adobe.com/xap/1.0/" xmpMM:DocumentID="E5DE28DC62AFBBA8D54ED4260CA8F582" xmpMM:InstanceID="xmp.iid:8d5ed2dc-16d8-4b7b-ab48-b50ceffc44db" xmpMM:OriginalDocumentID="E5DE28DC62AFBBA8D54ED4260CA8F582" dc:format="image/jpeg" photoshop:ColorMode="3" xmp:CreateDate="2017-06-29T11:36:29-04:00" xmp:ModifyDate="2017-06-29T11:37:31-04:00" xmp:MetadataDate="2017-06-29T11:37:31-04:00"> <xmpMM:History> <rdf:Seq> <rdf:li stEvt:action="saved" stEvt:instanceID="xmp.iid:8d5ed2dc-16d8-4b7b-ab48-b50ceffc44db" stEvt:when="2017-06-29T11:37:31-04:00" stEvt:softwareAgent="Adobe Photoshop CC 2015 (Macintosh)" stEvt:changed="/"/> </rdf:Seq> </xmpMM:History> </rdf:Description> </rdf:RDF> </x:xmpmeta>

yes :)
id="646374667b3362306261347d"?>

"646374667b3362306261347d".decode("hex")
'dctf{3b0ba4}'