Malicious PDF — malware analysis report

Static analysis result for SHA-256 e55b1009ed842d39…

MALICIOUS

PDF

64.0 KB Created: 2021-09-25 17:26:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ceeffa9082972a9a593500e12fa5ece0 SHA-1: e6f67d08832b991f87a053b6f2f675f598c87a8e SHA-256: e55b1009ed842d394cff0938cec445853708c51548faba254fcb4b5ae59886f9
194 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous heuristic firings indicating it is a link farm, with many links pointing to compromised WordPress sites or disposable hosting. The ClamAV detection and ML classifier also flagged this PDF as malicious, likely due to its nature as a phishing or malware distribution lure. While no scripts were directly extracted, the structure and numerous external links strongly suggest an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6457

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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
  • 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://chip-chup.hu/upload/file/62867911982.pdf In PDF document text
    • https://learnrkbin.jugalbandiresearch.com/ckfinder/userfiles/files/27801506327.pdfIn PDF document text
    • http://baovephuongtroi.com/vietkiendo/upload/file/fixinuxofewujosopirubexox.pdfIn PDF document text
    • http://lapempi.nl/ckfinder/userfiles/files/84326763254.pdfIn PDF document text
    • https://www.medicalbi.com/ckfinder/userfiles/files/bujanipibubinale.pdfIn PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b50b9c56f1---71922124261.pdfIn PDF document text
    • http://montoaneli.com/ckfinder/files/53356464366.pdfIn PDF document text
    • https://resulgame.com/calisma2/files/uploads/93482808450.pdfIn PDF document text
    • https://www.truckersplantparts.co.uk/ckfinder/userfiles/files/79962458456.pdfIn PDF document text
    • http://antwerp-reefer-tournament.be/argt/files/lusimifej.pdfIn PDF document text
    • https://europartner2.pl/uploads/vironu.pdfIn PDF document text
    • http://industra.sk/userfiles/file/55407129943.pdfIn PDF document text
    • http://tksvolga.ru/userfiles/file/vokevizaborujafalawasum.pdfIn PDF document text
    • http://zhfangyuan.com/uploadfiles/files/xasaxamap.pdfIn PDF document text
    • https://muzeumkonstancina.pl/attachments/file/31367518154.pdfIn PDF document text
    • https://phr4u.com/files/bijiwemulowe.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fe1387dd14---354431627.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161436bb15e875---jamexesuwitotapit.pdfIn PDF document text
    • http://unipsyclinic.com/userfiles/file/20210925212732.pdfIn PDF document text
    • http://studiomedicoveterinariobellucci.eu/userfiles/files/zefulesozuduninuzakazosuk.pdfIn PDF document text
    • http://joltiy.ru/uploads/files/74949432952.pdfIn PDF document text
    • http://scard.vn/app/webroot/uploads/files/xogusixumap.pdfIn PDF document text
    • http://weighlessthisyear.com/ckfinder/userfiles/files/14701282902.pdfIn PDF document text
    • http://www.binghan.my/userfiles/file/zusitazotoruk.pdfIn PDF document text
    • http://gr-chem.com/upload/files/65225395635.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=basic+chords+of+kabilang+buhayPDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bce3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBCE3 11024 bytes
SHA-256: 2a322f53cf48e55fe6fa8d6c4a3fdcf076a9df902526a7df3beb4920aa2b4217
font_01_sfnt_off0000d640.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD640 18248 bytes
SHA-256: 17d3e4a4955aa28747237d38eeb64a172f701620b763a329534dbf2d14af3445