Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6c6e396fb14d91b…

MALICIOUS

PDF

82.2 KB Created: 2021-09-20 17:24:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e261949ecc47d621d6bc9d56104d5693 SHA-1: a66a6fa85816efc861cc3ac1ab0ccefba4802702 SHA-256: f6c6e396fb14d91ba77c2e2795a074d3160f389f37917552147f7828c5b38df4
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs and is flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM indicates a large number of links pointing to disposable domains, suggesting an attempt to distribute malicious content or phish for credentials. While no scripts were explicitly extracted, the PDF structure and embedded links strongly suggest it's designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/7c9c7ac633208057d07e7e43bb08ab21/legibiw.pdf In PDF document text
    • http://daehnfeldt.com/userfiles/file/95496293648.pdfIn PDF document text
    • http://brbud.pl/userfiles/file/60192509438.pdfIn PDF document text
    • http://mamtaniketan.com/userfiles/file/gipisojewutofunig.pdfIn PDF document text
    • https://pianotuningdarwin.com/userfiles/files/92294653077.pdfIn PDF document text
    • https://bravo-hk.com/userfiles/file/21987292727.pdfIn PDF document text
    • http://basketaci.cz/UserFiles/File/rakafamavusikuzemewivak.pdfIn PDF document text
    • http://ammk.sk/userfiles/file/dekumimukiku.pdfIn PDF document text
    • https://girisimhaber.com/uploads/file/4613817628.pdfIn PDF document text
    • http://aedjtjdshbf.pretty-match.com/upload/files/povorevuzobaxabiw.pdfIn PDF document text
    • https://valgott.com/images/userfiles/file/jebefapezeguped.pdfIn PDF document text
    • http://carrollcountylawyers.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gupewusaxosagib.pdfIn PDF document text
    • https://casasholidays.com/scgtest/team-explore/uploads/files/bidolizagalukufedun.pdfIn PDF document text
    • http://yokosohk.com/files/fckfiles/file/ravudevabanaturalunu.pdfIn PDF document text
    • http://mnogonomerov.ru/uploads/file/soboxepezubiladiwo.pdfIn PDF document text
    • http://mistral-paints.cz/userfiles/files/7089283815.pdfIn PDF document text
    • http://cjmfgxfollow.morefriendship.com/upload/files/polatawixukuzefewajono.pdfIn PDF document text
    • http://rujiahk.com/uploadfiles/file/fofevenizevusagojamiwi.pdfIn PDF document text
    • http://maulich.vn/attachment/files/zipuzapojibavik.pdfIn PDF document text
    • http://zovsh.com/Uploadfiles/files/23343002504.pdfIn PDF document text
    • http://thainightjob.com/ckfinder/userfiles/files/96946691127.pdfIn PDF document text
    • http://www.specemc.ru/upload/files/1125835147.pdfIn PDF document text
    • https://seeandhearbetter.ie/img/shop/contents/9521230490.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=alert+notification+androidPDF 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_off0000dd1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD1F 18172 bytes
SHA-256: da333e53544c95e624af473287999c8757567a365e5023fa9d1ce6103f4e75e7
font_01_sfnt_off00010bd4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BD4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000123eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123EB 10284 bytes
SHA-256: 7fe94d9fde8ad9c825cb09e1993a4754e0cb09f99ba6b2424ab13cde9259b80b