Malicious PDF — malware analysis report

Static analysis result for SHA-256 f52f4b4c4b662132…

MALICIOUS

PDF

88.1 KB Created: 2021-06-28 15:07:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 30d7fca18815f8e9e59ccf1a6adc8226 SHA-1: 5b42168ddced1a6ba9471df2834ca2fdb516ae54 SHA-256: f52f4b4c4b66213225101c6b93fa4eb198432811f6bda641ec37a74309510545
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 ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, pointing to numerous compromised WordPress upload directories and disposable hosting sites. These links likely serve as redirects for phishing or malware delivery, a common tactic for initial compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/41ff9d78253afb2ce90b29c166beff99/kavidul.pdf In PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/b2797bcbb44e05784dc18e5d1ea3666e/tipikoxi.pdfIn PDF document text
    • http://tafoto.de/img/upload/files/96903696602.pdfIn PDF document text
    • https://advancedcheckcashadvance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607843ed4041e---12717369358.pdfIn PDF document text
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/k38chqkn3r7pc7opacu0irhjmf/katejuru.pdfIn PDF document text
    • https://olivier-daulte.com/ckfinder/userfiles/files/38925800071.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160cf946cb4a42---15361659677.pdfIn PDF document text
    • http://wmc21.com/ckupload/files/75070304265.pdfIn PDF document text
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078881d2254f---nuramenejafudejone.pdfIn PDF document text
    • https://gertiesbloomers.com/kousumi/nulook/upload/fckimages/file/30535503480.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/068b3a1666f00227b63b9dbb80cfe708/neluvajuguzovoru.pdfIn PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/44qu7hjelv23cl3r16j8c9csbk/wiket.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9e8949eec6---bodof.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/160cfcb62a1e37---jiwuzowexezaxugadazede.pdfIn PDF document text
    • http://cafegreenwichvillage.com/uploads/files/zuzojam.pdfIn PDF document text
    • http://vivaibonomo.it/userfiles/files/zaxafogose.pdfIn PDF document text
    • http://taxilitomerice.cz/ckfinder/userfiles/files/dijux.pdfIn PDF document text
    • https://stegopackaging.com/wp-content/plugins/super-forms/uploads/php/files/mljfc4j2bkkab4qa6nh4to399j/mebeberodepuro.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16092973ee1d60---70498470179.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/looe8jplsklrra05uevrftbbe1/renesu.pdfIn PDF document text
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/b5c44720e27ecdfe5404efd091499f38/76685836688.pdfIn PDF document text
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/fbe472650811c61d1b2f6ae57fa1899e/wodegexurixotiwilu.pdfIn PDF document text
    • https://www.kadinlarsitesi.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606ff885da099---kujanisajekugevajabafer.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/535aa475f42fe021863cae1bf6dd6021/5086441342.pdfIn PDF document text
    • http://alsumiri.net/wp-content/plugins/super-forms/uploads/php/files/7b82ade51562f40b79701e231d96c71e/dobiwix.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16087494a5cf33---mepolipugapo.pdfIn PDF document text
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160908000a83e0---26571750063.pdfIn PDF document text
    • http://m-camper.ru/ckfinder/userfiles/files/mozobivesowafotikilulepab.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=construction+accident+attorneyPDF 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_off0000f716.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF716 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010f2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F2D 10560 bytes
SHA-256: 4f5974f1054f861d93d6d6c1dde44e224c20cc0eb66f389dda1166dd9e2e7b0f
font_02_sfnt_off00012777.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12777 16624 bytes
SHA-256: fda8dd8fb8b6f00978aa0ec396d4134b68cc07a792871ddd0b5fb4120b6045ed