Malicious PDF — malware analysis report

Static analysis result for SHA-256 e71a92c7a73c8b23…

MALICIOUS

PDF

79.1 KB Created: 2021-09-10 16:15:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 55e222ce71509b3f962120b4d80fb2f8 SHA-1: e70a85d0766a705293bd1437fb356cbd1c6d6f6b SHA-256: e71a92c7a73c8b237f144516af7b4a83b20b1f4af2af078a822ef90e59cc4f33
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file is identified as a malicious PDF by ML classifiers and ClamAV. It functions as a link farm, with numerous embedded URLs pointing to compromised or disposable hosting domains. The primary purpose appears to be directing users to potentially malicious content or phishing sites, leveraging the compromised CMS upload storage for some links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://www.sindafaz.com.br/admin/editor/ckfinder/userfiles/files/retajebenurafoxiz.pdf In PDF document text
    • http://tinhdauvietnam.vn/upload/files/36691486425.pdfIn PDF document text
    • http://ratchadatitan.com/UserFiles/File/ruzobinomogifowuw.pdfIn PDF document text
    • https://culturasiapamplona.com/guiarte_userfiles/files/38841751691.pdfIn PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16133799c89d35---9696048991.pdfIn PDF document text
    • http://on-video.com/movies/movie_data/file/36774683817.pdfIn PDF document text
    • https://foodsafebox.com/ckfinder/userfiles/files/bitumetarofotevepizimowov.pdfIn PDF document text
    • http://ketphatthinh.vn/upload/files/38806155063.pdfIn PDF document text
    • http://asqcert.net/files/files/sovevonizurititozovaburu.pdfIn PDF document text
    • https://doctorchina168.com/upload/files/kulaxofuvidu.pdfIn PDF document text
    • http://h-p-n.fr/catalogue_dynamique/file/soruvadovalebudifesabe.pdfIn PDF document text
    • http://www.mariabeckmann.com/fotos/uploads/files/31683817630.pdfIn PDF document text
    • http://eugensa.lt/app/webroot/uploads/userfiles/files/timajiwinalabe.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16135c48348184---vavutudubatafixoj.pdfIn PDF document text
    • http://topbondtape.com/uploadss/file/46847570028.pdfIn PDF document text
    • http://archinfo.ru/uploads/file/23524835476.pdfIn PDF document text
    • http://myslizdrave.com/soubory/15163753954.pdfIn PDF document text
    • https://ambient-interier.cz/files/files/rotejidenajixenudepew.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/mp8upjphjd38tmcchv27fqs1s0/xiduk.pdfIn PDF document text
    • https://stradatextiles.com/upload/ckfinder/files/12898579331.pdfIn PDF document text
    • https://sabagdasarov.ru/upload/file/wozomiwelarew.pdfIn PDF document text
    • http://obraz-tlt.ru/userfiles/file/piluledu.pdfIn PDF document text
    • https://nepalihemp.com/ckfinder/userfiles/files/63050101555.pdfIn PDF document text
    • http://halongbaycruises.org/upload/files/47603685832.pdfIn PDF document text
    • http://montpellier-business-plan.fr/mbp/upload/images/images/upload/ckfinder/21083971380.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=my+hero+academia+heroes+rising+free+englishPDF 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_off0000c9c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9C0 19804 bytes
SHA-256: 7b7c5aebeee802bf772e7e3755e1c9d4c39940a2a31b87ff73b858c0bba8aebf
font_01_sfnt_off0000fd5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD5A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011571.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11571 10932 bytes
SHA-256: f0786452b939d8879471fedbc199f52fe83aa514f5d2151d6e207e7841d1a475