Malicious PDF — malware analysis report

Static analysis result for SHA-256 b971fcf8b26a13bf…

MALICIOUS

PDF

80.0 KB Created: 2021-09-12 10:46:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: f8fb84cb880360b1b1ff189c1af5a9a8 SHA-1: c3fa1534b1e072a6b8b1991cfbd4a91046c0567d SHA-256: b971fcf8b26a13bf54c24bb30e4588cae2b5789478c2524a54d921effd3d9de9
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised CMS upload locations and disposable hosting, indicating an attempt to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is unreadable due to encoding, but the heuristics and URLs clearly point to a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/d91a53081b92ec37c764e7e88e80ff21/nejuselos.pdf In PDF document text
    • https://valserve.in/web/k/main_admin/ckfinder/userfiles/files/zodiral.pdfIn PDF document text
    • http://boldino-hotel.com/ckfinder/userfiles/files/6228208885.pdfIn PDF document text
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/8b9a65edb947bfb0e70d2e0cfe4d32af/21110102940.pdfIn PDF document text
    • https://www.lire-les-notes.com/ckfinder/userfiles/files/jowiketumejowokasep.pdfIn PDF document text
    • http://spalovnachemolak.sk/userfiles/file/kotupimolekijuwodigu.pdfIn PDF document text
    • http://cu-hinothai.com/ckfinder/userfiles/files/70310003405.pdfIn PDF document text
    • https://regiefranchet.fr/userfiles/files/daduzite.pdfIn PDF document text
    • http://texinpack.com/uploadfile/file///2021090116332862.pdfIn PDF document text
    • http://dastone.ru/userfiles/file/vegexakezizoxilu.pdfIn PDF document text
    • http://minhphucvietnam.com/uploads/userfiles/file/surijap.pdfIn PDF document text
    • http://omonetach.pl/foto/ilustracje/file/venebifaro.pdfIn PDF document text
    • https://vinadesigndanang.vn/uploads/image/files/6002726945.pdfIn PDF document text
    • http://saatgaamkansarasamaj.com/admin/uploads/files/93563208029.pdfIn PDF document text
    • https://stabiactiv.com/userfiles/file/fadipexupipozosuxa.pdfIn PDF document text
    • http://biosurfest.com/userfiles/files/fukulera.pdfIn PDF document text
    • http://dgelc.com/userfiles/file/20210906104421.pdfIn PDF document text
    • http://busankid.com/webfiles/board/file///voxodowopu.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613407d6c95ec---54586953875.pdfIn PDF document text
    • http://eros-arena.name/eros/userfiles/file/turotasadozilemi.pdfIn PDF document text
    • http://edituj.cz/res/file/moxofiboparirixuduj.pdfIn PDF document text
    • http://www.ambatownship.com/ckfinder/userfiles/files/92977786771.pdfIn PDF document text
    • https://egyseg.eu/ckfinder/userfiles/files/fefazoponumamaterudi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=super+crafting+and+building+2020+apk+downloadPDF 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_off0000d252.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD252 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ea64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA64 17400 bytes
SHA-256: 2f46b72b3a6753b6c865c1a4d1d2d830b749e33f4b83d3d374b5b850b86682e4
font_02_sfnt_off000117e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117E6 11364 bytes
SHA-256: a82232e61314d0fc359285cb9a8fa771aa5aaa155b1358c2b1da713225d5d331