Malicious PDF — malware analysis report

Static analysis result for SHA-256 66d72170a916f117…

MALICIOUS

PDF

84.8 KB Created: 2021-09-06 21:45:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 38923ce5fb42e6ea6bc865007f9c2f44 SHA-1: 01e1d17b8512d7345f37059b5d37b890be72fb72 SHA-256: 66d72170a916f117b802078954d6f43d9f1f93ddb5dad9946ddf6cf451321aec
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads and disposable hosting. The ML classifier strongly flagged this PDF as malicious. The primary function appears to be a link farm, likely intended to redirect users to potentially malicious sites or for SEO poisoning, rather than delivering a direct payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • 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 http://ausafe.net/images/art/files/83194276937.pdf In PDF document text
    • http://www.aadhar-interior.com/userfiles/file/lugalu.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d9de91e5cc---zafamudotilazil.pdfIn PDF document text
    • https://psystat.net/candyticket/uploads/page_images/files/sipogafixixabidafeme.pdfIn PDF document text
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160b5c1cf96261---97131913365.pdfIn PDF document text
    • http://streetnn.ru/data/upload/ck/files/98940179818.pdfIn PDF document text
    • http://innersolutions-uk.com/file/86456610954.pdfIn PDF document text
    • http://albino-pitti.com/pub_img/file/wajofedebarokitex.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ec9928feb2---13831234322.pdfIn PDF document text
    • http://twxcd.com/img-aim/files/62278432878.pdfIn PDF document text
    • http://bazatalty.pl/wp-content/plugins/super-forms/uploads/php/files/7bd22eca95b2900240a918103d554d1e/16121642224.pdfIn PDF document text
    • http://bekkercoon.ru/ckfinder/userfiles/files/54316399654.pdfIn PDF document text
    • http://mobiliteit.nu/files/10147890519.pdfIn PDF document text
    • https://nothingbutsafetyglasses.com/userfiles/file/jokaxewapegezama.pdfIn PDF document text
    • http://cancunday.com/travela/img/files/16142151215.pdfIn PDF document text
    • https://hchoanglong.vn/userfiles/file/81223899615.pdfIn PDF document text
    • http://vetportonaccio.it/userfiles/files/xiviwewudob.pdfIn PDF document text
    • https://adium.ru/userfiles/file/kaxevakumefe.pdfIn PDF document text
    • http://coeb.eu/userfiles/files/86315319048.pdfIn PDF document text
    • http://axiomestates.com/userfiles/file/zimudowafu.pdfIn PDF document text
    • https://mttrasportisrl.it/dati/upload/file/bowimovetib.pdfIn PDF document text
    • http://physocare.com/Images_upload/files/sexorutabozigilogakadipob.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607eae63f2371---jozezegonubitemupomuba.pdfIn PDF document text
    • https://loctra.net/userfiles/file/kanav.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=overlapping+intellectual+property+rights+pdfPDF link annotation
    • 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_off0000e5c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5C1 11204 bytes
SHA-256: 64e0584e19a4ec95ab8950136baa80092a3b701708455ba9d6ee800629eb23cd
font_01_sfnt_off0000ffc6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFC6 17616 bytes
SHA-256: 8e0cc75420998fc28571c7c5b58b6d51204a1824fa6015e9cdda23cf59db100f
font_02_sfnt_off00012d56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D56 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1