Malicious PDF — malware analysis report

Static analysis result for SHA-256 89d11f8af29b5877…

MALICIOUS

PDF

94.0 KB Created: 2021-09-21 20:00:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: dcd3a29f697228a2ec8eead0f61ca4b1 SHA-1: bee5a631c1306a4a0a9dfa235dadae7976ba2664 SHA-256: 89d11f8af29b5877affbfbe839af91462ec1ee88328d486bad8c1a5b3279ebba
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple unknown or potentially compromised websites. The presence of numerous PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM firings strongly suggests the document's purpose is to host a collection of links, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f5c02536ed.pdf In PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/3nst192mpn8n6fgrl64gc32dr4/rawukapazejewozenat.pdfIn PDF document text
    • http://nakajima-ya.com/upload/save_image/files/matajifugi.pdfIn PDF document text
    • http://ijfbn.com/editor_up/korika.pdfIn PDF document text
    • http://idcla.net/upload/files/89021422654.pdfIn PDF document text
    • https://luckysurface.itweald.com/uploads/files/61485865ab8d7.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131307d943a5---5211278437.pdfIn PDF document text
    • http://obraz-tlt.ru/userfiles/file/kotegirulegoloja.pdfIn PDF document text
    • http://cdseoulps.com/uploadfile/fckeditor/file/1190548005.pdfIn PDF document text
    • http://apvn.info/userfiles/file/zafizipakaf.pdfIn PDF document text
    • http://paykaaluminiya.ru/ckfinder/userfiles/files/66270784193.pdfIn PDF document text
    • http://schokobrunnen.com/idata/27794731339.pdfIn PDF document text
    • https://infotechb2blite.com/bot/ckfinder/uf/files/niwopevexulajigidevoj.pdfIn PDF document text
    • https://marugame.hk/editor_upload/file/repusalevim.pdfIn PDF document text
    • https://www.tahitotfalu.hu/ckfinder/userfiles/files/68591959592.pdfIn PDF document text
    • https://akgoz.zemta.com/uploads/files/1133070367.pdfIn PDF document text
    • http://brianhaymore.com/images/e/file/39303633966.pdfIn PDF document text
    • https://www.renfrewareahealthvillage.ca/ckfinder/userfiles/files/sivasigukomesoz.pdfIn PDF document text
    • http://fine-cottage.ru/userfiles/file/jikisavorurarodogus.pdfIn PDF document text
    • http://hyunshin.net/userfiles/file/98893307209.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/44585916e63266f9c903133f8154c4df/wexetut.pdfIn PDF document text
    • http://mjacz.cz/soubory/files/wuvupidafadewufobigogo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=3.5+magic+item+compendiumPDF 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_off0001052d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1052D 19636 bytes
SHA-256: 008d8fc487e5fde8c9a6256609e322520182b9f641574f59bb4537ebf008ec78
font_01_sfnt_off000139a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139A4 10916 bytes
SHA-256: f081958118a24abfa222e2cf167398c914121e3f431e7693041e7c06d3f10d0a
font_02_sfnt_off000152b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x152B2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1