Malicious PDF — malware analysis report

Static analysis result for SHA-256 3fec94c34a640621…

MALICIOUS

PDF

81.6 KB Created: 2021-09-18 20:58:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d1a0c273e4fe0d2546b89dcdb491030b SHA-1: 7b0d60a41a075834554b24fe0df08206ef06ca45 SHA-256: 3fec94c34a640621a4d8d579f89abae12ccd387826c865b8c9c3f314ed36b5fd
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating it likely contains malicious content. Heuristics reveal it functions as a link farm, with numerous URLs pointing to compromised CMS upload directories and disposable hosting. The presence of these links suggests an attempt to redirect users to malicious sites for phishing or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/c878b1864ea31fdfcf206a37b8ac0fc2/13458555515.pdf
    • http://mtkshop.com/images/uploads/file/12694964819.pdf
    • http://ersenergy.com/UserFiles/file/naxasoza.pdf
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/2f7add3536c4643057bf8a2613b94337/98666204704.pdf
    • https://www.funes.gob.ar/ckfinder/userfiles/files/83354216677.pdf
    • https://buffinvestment.com/upload/ckfinder/files/42460178017.pdf
    • http://placidlakes.com/larpm/uploads/file/gaxixarenu.pdf
    • https://ketex.com/trcgp/ckfinder/userfiles/files/xawupopisipanesubizow.pdf
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130b344da5c6---bofibevigafevemaz.pdf
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/161436f562aa6d---39049174778.pdf
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613931c71428c---9591580061.pdf
    • http://detaycopymatbaa.com/userfiles/file/18299769117.pdf
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/15ga7us0075udob31ut3fhnuj1/85937595687.pdf
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a11471cfbd---14804714838.pdf
    • http://ginzaramen.us/uploads/files/38442633657.pdf
    • https://www.idd.no/ckfinder/userfiles/files/55414971125.pdf
    • https://mobspace.xyz/web/img/podborky/files/kazitarebijizonadumuvi.pdf
    • http://sistarelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/61597985551.pdf
    • http://chinahk-ip.com/chinahk_ip/html/files/editor/file/wiwij.pdf
    • http://web5gstore.com/Files/files/biwulabexenukodolatexejer.pdf
    • https://duragloss.pl/userfiles/file/45666107283.pdf
    • http://sun-apartments.pl/data/pages/mazirokeduxiwo.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=best+css+framework+for+react
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000de3e.bin
da65e0b3ce260e42339170a4cfe83a349223171eec566e582130fb47090216b9
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE3E 16628 bytes
font_01_sfnt_off000108ed.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x108ED 16792 bytes
font_02_sfnt_off00012104.bin
268f1c8d173ec36683eca4f0636024dfab32a3135c96ac4ea6234f88b3fe1a90
pdf-font-stream PDF embedded font (sfnt) at offset 0x12104 10488 bytes