Malicious PDF — malware analysis report

Static analysis result for SHA-256 8da881e981653894…

MALICIOUS

PDF

82.2 KB Created: 2021-09-07 14:15:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: aaf8fee31ed698290f4f1946c90ed08c SHA-1: 2c6c9722454bf5a8f8c2388f49e898d4539edb92 SHA-256: 8da881e981653894521eb75f785a071cb4b2d6e202b317129acb38ea24434aae
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous links, many pointing to compromised WordPress upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic strongly support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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://www.aadhar-interior.com/userfiles/file/42643536868.pdf In PDF document text
    • https://amblamy.ee/upload/file/91270682534.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/160bf18d589891---nulefomizabobu.pdfIn PDF document text
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/a074d2d8c489aaffbadcad3d7421f3e4/34749495547.pdfIn PDF document text
    • http://flightshop.jp/images/blog/file/35964791275.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fead488f8e---pavikedofofukuxufi.pdfIn PDF document text
    • https://snqrsl.quebec/upload/editor/file/45809260004.pdfIn PDF document text
    • http://servmed.net/userfiles/file/33025173771.pdfIn PDF document text
    • http://www.yemany.com/yemfiles/files/lewimik.pdfIn PDF document text
    • http://huerural.com/uploads/image/files/kipomudiwonaxawasok.pdfIn PDF document text
    • https://soudurelauziere.ca/upload/editor/file/xazetebevewapuwisifafov.pdfIn PDF document text
    • https://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/5a4aceab83420e4cb49e5ac0962dcc24/81620945723.pdfIn PDF document text
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/6ad09a85ed63cf332b6b46df52824054/37713157972.pdfIn PDF document text
    • http://quatanggiabao.com/images/uploads/files/masetusefesetejazopexexu.pdfIn PDF document text
    • http://tykhestudiodesigns.com/clients/7/73/7311521ca682816632878891c231d107/File/13193551573.pdfIn PDF document text
    • http://eko-inwest.eu/upload/file/molapasivigudewofo.pdfIn PDF document text
    • https://uleshuzataruhaz.hu/files/file/mubaruxubenojabaxubesaru.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c6ab2208d2e---disafukezap.pdfIn PDF document text
    • https://debo-fit.be/userfiles/file///gufuxipizil.pdfIn PDF document text
    • https://shopabrang.com/images/files/pifenufotiminativitefoni.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/1607f1f8104c00---18583624657.pdfIn PDF document text
    • http://teusz.pl/UserFiles/file/vijiretajanumesozi.pdfIn PDF document text
    • http://evpltravel.com/xv_image/file/47339888139.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084a9ef64280---dezaxufoxowa.pdfIn PDF document text
    • http://anatolianlgs.com/userfiles/file/dozirigodaxugofebibepa.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/160832378cb781---99060546249.pdfIn PDF document text
    • http://incomsistema.ru/ckfinder/userfiles/files/jetonilozo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=livro+boca+do+inferno+em+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_off0000d9e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9E5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f1fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1FC 10632 bytes
SHA-256: 956b48f9ac17243721368c3540de591502e135c6fcda1a43f1d60ef57affa863
font_02_sfnt_off00010a14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A14 19224 bytes
SHA-256: 4cae4dd44dc0eb98ed473238511238675b3c1f47ee2a01041de50a3eca22cd60