Malicious PDF — malware analysis report

Static analysis result for SHA-256 a91c365b7eb9fa78…

MALICIOUS

PDF

70.6 KB Created: 2021-09-24 13:01:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: bbb02788aaf1c2b0c97575adf3f014ca SHA-1: 425205ebe3b9a61bbe1758ef992f3f2cb82a3300 SHA-256: a91c365b7eb9fa78758db1f2a7d921e34a67c80e1eaad6ceb92b50b45487ffa3
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified the document as a link farm, with numerous URLs pointing to potentially compromised websites or disposable hosting, suggesting an attempt to redirect users to malicious content. The presence of external URIs and link farm characteristics strongly indicates a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://zaragozalawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/46934229517.pdf
    • http://rebeccafantarchitetto.it/userfiles/files/612735394.pdf
    • http://ramenhajimetustin.com/uploads/files/25325429671.pdf
    • https://hurghadalife.net/userfiles/files/sositagokoniziteson.pdf
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161364948874b3---13172366990.pdf
    • http://uslugi-ogrodnicze.pl/pliki/File/31510312622.pdf
    • https://suacuachuyennghiep.com/uploads/files/resuduridog.pdf
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/67dqoc69bircua8ns4cnpe8cda/fofon.pdf
    • http://northmarking.com/userfiles/files/xedagevivuvelupijasosed.pdf
    • http://dydlhx.com/upfiles/file///37573272145.pdf
    • http://zechnerbau.at/images/content/files/tevaledojas.pdf
    • http://udelimpa.es/ckfinder/userfiles/files/93590870069.pdf
    • https://testpensija.bankai.lv/ckfinder/userfiles/files/tupodamututiludoj.pdf
    • http://ordinate-ltd.com/file_media/file_image/file/lekesowafasudamaf.pdf
    • http://vattuxaydunghl.com/userfiles/file/binitebaledifokateta.pdf
    • http://squarcialupirelaxinchianti.com/writable/public/userfiles/file/78391490852.pdf
    • http://haai.org/upload/file/1421400579.pdf
    • http://3e3i.com/UserFiles/file///xawakologupeji.pdf
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/245b05ae9df7ab5e395b8a2252ad684d/7193016912.pdf
    • http://fine-cottage.ru/userfiles/files/nifilomawos.pdf
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16144d5a609002---16476101665.pdf
    • http://bhartiyambeohari.in/userfiles/file/guzeraxoturevomofuwisip.pdf
    • https://qpshouse.com/upload/image/file/madizotukugax.pdf
    • https://leifs-auto.dk/images/file/35651169320.pdf
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614989cca9451---97678731842.pdf
    • http://resetimpianti.it/reset/public/file/20865070798.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=android+cracked+software
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b583.bin
6088ae9a237ec9eba5b9e7299f2cb375ad2277319e53a565774fcc58971ece58
pdf-font-stream PDF embedded font (sfnt) at offset 0xB583 10584 bytes
font_01_sfnt_off0000cde8.bin
8b902c9ee162af8e975f52cbce04480b9ef261b145913de42627e642aa2ad850
pdf-font-stream PDF embedded font (sfnt) at offset 0xCDE8 15164 bytes
font_02_sfnt_off0000f487.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF487 16792 bytes