Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fcaca9087c2a515…

MALICIOUS

PDF

82.1 KB Created: 2021-09-03 09:04:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 71271ee4fa626c3774811166e01e7ce4 SHA-1: fc4c499068038fdb1d5fb90d88d12373e2599a6f SHA-256: 8fcaca9087c2a5158a96a137a1847150b354aa16bc4616faddb630982c0efad4
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of links, many pointing to compromised WordPress sites and other disposable hosting. The ML classifier strongly indicates maliciousness, and the link farm structure suggests an attempt to manipulate search results or distribute further malicious content. No scripts were extracted, but the overall structure points to a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • 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://hcvitamin.com/webroot/img/files/tironalilo.pdf In PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16076b9aea4dc0---maweguwurujosaxobuxola.pdfIn PDF document text
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/8fa1abe48227da4b836cbb75382f7fcd/59449724344.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b83de6ae5aa---69841134124.pdfIn PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608326fade988---49766855756.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/52229864435.pdfIn PDF document text
    • http://idroter.org/userfiles/files/volasebikemizuto.pdfIn PDF document text
    • https://xn--22ck6bdp5cach0mc23a.com/ckfinder/userfiles/files/25986723183.pdfIn PDF document text
    • https://iamtimeshare.com/userfiles/file/zifur.pdfIn PDF document text
    • http://sicilalluminio.it/userfiles/files/ruruvipek.pdfIn PDF document text
    • http://sccsfz.org/upload/11800711730.pdfIn PDF document text
    • https://eandjfamilyhealthcenter.com/wp-content/plugins/super-forms/uploads/php/files/ab9ce0df011c8416351f0bb304714a88/70334213594.pdfIn PDF document text
    • https://marathonroller.com/userfiles/files/38281084550.pdfIn PDF document text
    • http://baocaosuhoatoc.com/luutru/files/69607222406.pdfIn PDF document text
    • http://worldnaturalfood.com/image/upload/File/radamex.pdfIn PDF document text
    • http://unicorn-furnitures.com/d/files/5179861279.pdfIn PDF document text
    • https://borgopitti.it/userfiles/file/33679991586.pdfIn PDF document text
    • https://carmelocuritiba.com.br/ckfinder/userfiles/files/71238570587.pdfIn PDF document text
    • http://scheiden-maassluis.nl/uploads//file/33854049854.pdfIn PDF document text
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/5ee18704266288ee1faa9e343216cf85/sugirirusonil.pdfIn PDF document text
    • https://alsultantrading.ae/userfiles/files/41219670702.pdfIn PDF document text
    • https://monacollection.ua/wp-content/plugins/super-forms/uploads/php/files/ec581e11f02dc383bc9d8f003b3d430d/73573790483.pdfIn PDF document text
    • http://tafgambiatours.com/userfiles/file/60565932792.pdfIn PDF document text
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/18f78ee5f7dcdf60d8b8b56c1a089f90/mimarajos.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=zelda+breath+of+the+wild+art+book+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_off0000d8dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8DD 10604 bytes
SHA-256: 3def85574ea4ddaa2d93a728d68419d1f24f2b1d44e90140d7b8cc12fb919e0f
font_01_sfnt_off0000f109.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF109 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001091b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1091B 19544 bytes
SHA-256: 5f78be47ec266d811b7e72ab8d8834f27c8af497c349b435bb352dbd2ac1de0a