Malicious PDF — malware analysis report

Static analysis result for SHA-256 d6941152d5ca5824…

MALICIOUS

PDF

87.5 KB Created: 2021-09-01 14:23:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: fe152d5dd12acdad355ac655383520c0 SHA-1: 65368a82cbef9122557a1b190eb8fbf16c51c405 SHA-256: d6941152d5ca58245e6d91fe15b86896d7bde14add5193fb5b70916592c1daea
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is unreadable binary data, but the heuristics clearly identify the file's function as a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://meijialx.com/ckfinder/userfiles/files/62610057698.pdf In PDF document text
    • https://ankaratemizlikcim.com/depo/sayfaresim/file/61415023780.pdfIn PDF document text
    • http://ankurgroups.com/userfiles/file/megotuj.pdfIn PDF document text
    • http://mrybalko.ru/files/bezejodu.pdfIn PDF document text
    • http://dzbnf.com/upload/file///vanoxebisoweneragupajak.pdfIn PDF document text
    • http://think6.net/ckfinder/userfiles/files/20210816153101.pdfIn PDF document text
    • http://lahma.pl/_u/userfiles/file/foponezotepegopebok.pdfIn PDF document text
    • http://china-baby-clothes.com/d/files/zagunomededafeveriravela.pdfIn PDF document text
    • https://tdfstore.it/file/bupajud.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1609b698059797---kiputuzogate.pdfIn PDF document text
    • http://gmicropilotes.com/uploads/files/48208292004.pdfIn PDF document text
    • http://albatrossmrn.com/konadnew/userfiles/file/felet.pdfIn PDF document text
    • http://timandlor.com/userfiles/file/lirarinoza.pdfIn PDF document text
    • https://marwaautorepair.com/nbloom/fckuploads/file/xavebasonex.pdfIn PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/8f015e1f8b094628d08b74c99f262a06/gomirixu.pdfIn PDF document text
    • https://condicionamentofisico.com/arquivos/file/rukemimaja.pdfIn PDF document text
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce3ed67ea4---nupedafirurugakajej.pdfIn PDF document text
    • https://sharjahcements.com/images/bulk_images/files/77068068998.pdfIn PDF document text
    • http://elma1.ru/!upload/files/xodegemijel.pdfIn PDF document text
    • http://xn--9d0b102a6wc3y4a.com/sa_upload/userfiles/file/20210702112800.pdfIn PDF document text
    • http://raegcafe.com/uploads/files/relunej.pdfIn PDF document text
    • http://daydreamspin.com/userfiles/file/14130702634.pdfIn PDF document text
    • https://europacreativaeuskadi.eu/files/galeria/files/52356879893.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/5q8u76lkpu3e1kulc7ui8liif5/rumunozemaxiduded.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=dr+ian+ong+paediatricianPDF 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_off0000f1a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1A1 10476 bytes
SHA-256: d299337cc59367deebc0269cdfb20347b9a500c55ba243f11855653bc93e1f2b
font_01_sfnt_off00010951.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10951 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012163.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12163 18272 bytes
SHA-256: fd09d708b073f0abb830feb0b830a0b73c91ede8d81eb642e24859d8f9d30ccf