Malicious PDF — malware analysis report

Static analysis result for SHA-256 13b337e398438697…

MALICIOUS

PDF

83.8 KB Created: 2021-09-16 21:11:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: c64b133db19f4d48563c8cfaf48fd3e8 SHA-1: 1edaacc60efbeb65785a221a5f068e1a8f5addde SHA-256: 13b337e398438697ac19480329f8ec90ef7727a17c539a0f2556c86db15a58be
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many hosted on compromised websites or disposable domains, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, but the PDF structure itself is used to host and distribute these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://coretry.ru/uplcv?utm_term=hp+murah+snapdragon+660 PDF link annotation
    • http://epoptavky.com/is/images/FCKeditor/File/47600027567.pdfIn PDF document text
    • http://autovoda.ru/upload/files/janupukugakadofivufakofes.pdfIn PDF document text
    • https://gmnavarra.es/ckeditor/files/zazodorufutigedalopati.pdfIn PDF document text
    • http://studioriboldi.eu/userfiles/files/52654819058.pdfIn PDF document text
    • http://gimhaejazz.com/fckeditor/userfiles/image/vezalatibogegoruv.pdfIn PDF document text
    • http://termosystem.pl/userfiles/file/xozusi.pdfIn PDF document text
    • http://himalayakebab.com/shipinc/userfiles/files/kelizoxusaxujenape.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/161427068e93ae---velosoxemexatokefudi.pdfIn PDF document text
    • https://www.speeddating.lt/speeddating/ckfinder/userfiles/files/64571814585.pdfIn PDF document text
    • http://icloudcleaners.com/uploads/account/autoresponderfiles/vexetejabawujove.pdfIn PDF document text
    • http://ps-chiptuning.hu/userfiles/files/49797323775.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/sb5d82s963tbni41d4umhcm3ef/noxediwupibitowigenenod.pdfIn PDF document text
    • https://fsbulletsandbrass.com/userfiles/files/9830264797.pdfIn PDF document text
    • http://hanmih.com/userfiles/file/20210911012121.pdfIn PDF document text
    • http://kiajihlava.cz/UserFiles/File/36857651278.pdfIn PDF document text
    • https://hantverksakuten.se/ckfinder/userfiles/files/zulelajumetilokag.pdfIn PDF document text
    • http://www.hermosabeachbungalows.com/userfiles/files/45042277055.pdfIn PDF document text
    • http://clair-environnement.eu/catalogue_dynamique/file/bojatijemugukasiwixakuj.pdfIn PDF document text
    • http://relaxzenter.com/uploads/files/21478620719.pdfIn PDF document text
    • http://mijinmotor.com/fckeditor/userfiles/file/fusamufogarefipuvel.pdfIn PDF document text
    • http://www.rify.us/cms-uploads/files/42244050092.pdfIn PDF document text
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/eb88ae0d878e2a47088f60dcf3a290ba/78390089432.pdfIn PDF document text
    • http://oldmotorsclub.com/files/file/17336740773.pdfIn PDF document text
    • http://chickenwild.com/upload/contents/images/images/gilasanidijimida.pdfIn PDF document text
    • http://gartenmessebau.de/uploads/files/xikewosenalupalotasunax.pdfIn PDF document text
    • http://yljczl.com/uploadfile/20210907073107767.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e283.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE283 10852 bytes
SHA-256: 14069ff09be6e35fa6bcf234c50a88ec1228c2ff79d4b9f794f3133c58d84951
font_01_sfnt_off0000fb05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB05 17948 bytes
SHA-256: b7ad87061f35efca9f9ed7d1de6cc19e9f482ea029d56854031f60ed6b7f4990
font_02_sfnt_off000129be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129BE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1