Malicious PDF — malware analysis report

Static analysis result for SHA-256 5ea505bfff381fca…

MALICIOUS

PDF

74.8 KB Created: 2021-09-15 12:26:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 155fe8b5500ed85d1daa651358613b1a SHA-1: 591b75e5e7079c393c017418116be85423031d4a SHA-256: 5ea505bfff381fcab226a48a943febd95b73e92b950cae74e1a07bf4edfb4647
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm pointing to numerous other PDF files hosted on various websites, some of which are identified as compromised CMS uploads. The ML classifier strongly indicated maliciousness. The primary attack pattern observed is the use of a link farm, likely for SEO poisoning or to distribute further malicious content, rather than direct user interaction within the PDF itself.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 https://catamma.ru/uplcv?utm_term=mandalorian+wallpaper+android PDF link annotation
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16140349406b5d---kukodevep.pdfIn PDF document text
    • http://konemara.hu/userfiles/file/6186290691.pdfIn PDF document text
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/0n7vh489n7m1eh3gbeui4vom23/fazedade.pdfIn PDF document text
    • https://patidarpalanpur.com/web/k/main_admin/ckfinder/userfiles/files/59016434394.pdfIn PDF document text
    • http://quetthe.com/upload/files/suleneforibetizewak.pdfIn PDF document text
    • https://dichvuketoansg.com/luutru/files/5665348266.pdfIn PDF document text
    • http://toitureetfacade.fr/data/Files/30420166924.pdfIn PDF document text
    • http://iucecb.com/files/file/dosomifumazazumuzegatila.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1614161a455d3e---26239900888.pdfIn PDF document text
    • http://rungruangsteel.com/public/upload/userfiles/files/xexamikexikusivutaxiroreb.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/96648510194.pdfIn PDF document text
    • http://only-svet.ru/upload/files/80136496705.pdfIn PDF document text
    • http://acmemask.com/upfiles/editor/files/rusomod.pdfIn PDF document text
    • http://praconsulgroup.ru/pict/file/nezinovupesaxegor.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/16134170c91942---88411799157.pdfIn PDF document text
    • http://terwaarde.be/ckfinder/userfiles/files/74739403467.pdfIn PDF document text
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/1rjh5vtsfk3gtenivfdcau6o5j/9084766750.pdfIn PDF document text
    • http://hicoweld.com/shop/fck_file/file/filasefujekotuvimoluralap.pdfIn PDF document text
    • https://12waktu.com/contents/files/4303666051.pdfIn PDF document text
    • https://underworldgear.com/upload/users/files/gokedevagutitiropov.pdfIn PDF document text
    • http://www.guus.edu.mn/ckfinder/userfiles/files/xudetadoxekowipepojuwam.pdfIn PDF document text
    • http://www.bluewhaleline.com/image/upload/File/84577638006.pdfIn PDF document text
    • http://99hospitalitygroup.com/ckfinder/userfiles/files/93971249679.pdfIn PDF document text
    • 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_off0000bf6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF6C 18284 bytes
SHA-256: 503983ca00d897c9f9168dd4c0afcab87cf412c7806f4923559a2a25d0bdbcd1
font_01_sfnt_off0000eea1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEA1 10196 bytes
SHA-256: fb4bd2569d4850850d5512499b84b02fd72ac2e7415dcfaacb0a3c79976b528f
font_02_sfnt_off00010585.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10585 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1