Malicious PDF — malware analysis report

Static analysis result for SHA-256 d71add404cf864ac…

MALICIOUS

PDF

68.8 KB Created: 2021-10-02 10:31:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 56c7c764bddb9e34c939788d68f16c1d SHA-1: 744eeac3e7552094f5602f9f80e5ee243fac47b1 SHA-256: d71add404cf864ac23999a812255429b197ec3eb403252f5708a690d5ff3afa8
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm on disposable hosting, with numerous links pointing to various PDF files. The presence of a PDF_SEO_DISPOSABLE_LINK_FARM heuristic firing strongly suggests a phishing or scam campaign designed to direct users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9893

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 http://kehlux.lu/userfiles/files/kesokubekapojupapinipu.pdf In PDF document text
    • http://zoekidsworld.com/userfiles/file/dufobitukezo.pdfIn PDF document text
    • http://www.aceitunasdelguadalhorce.es/ckfinder/userfiles/files/linipasum.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/9698822895.pdfIn PDF document text
    • http://alrabbancapital.com/file/files/wofevesijireluwuj.pdfIn PDF document text
    • http://xn--spreewaldpension-lbben-9lc.de/meineBilderAlbertGrundschule/file/fajivodomi.pdfIn PDF document text
    • https://hinaweb.com/upload/file/nisegabivajetijifekix.pdfIn PDF document text
    • http://www.highlandmetals.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161323bfb77a8c---zelipexosufox.pdfIn PDF document text
    • https://immo-macedo.lu/userfiles/files/nozupivuvomixibe.pdfIn PDF document text
    • https://et-auditing.com/userfiles/files/pitaborulevoxesidajagedu.pdfIn PDF document text
    • http://imdad-egypt.com/userfiles/file/guruvur.pdfIn PDF document text
    • http://hfengly.dk/skoleportalen/userfiles/file/kanal.pdfIn PDF document text
    • https://peusch.lu/userfiles/files/rusafogadavoj.pdfIn PDF document text
    • http://narzedziascierne.eu/Upload/file/xanodolokegiwe.pdfIn PDF document text
    • https://aljazeerahpetroleum.ae/userfiles/files/gurexigapozinamurimokug.pdfIn PDF document text
    • http://whitedwarf.ru/public/images/ckfinder/files/44487268854.pdfIn PDF document text
    • https://www.aukuras.org/ckfinder/userfiles/files/loveru.pdfIn PDF document text
    • http://pantryscan.com/123cars/imagefck/file/vapuzulakesilil.pdfIn PDF document text
    • http://misterholidaysanprisco.it/userfiles/files/28108521652.pdfIn PDF document text
    • http://humidorio.de/ckfinder/userfiles/files/gugawewadomerinozifaxo.pdfIn PDF document text
    • https://palet-school.com/files/files/sawuturawo.pdfIn PDF document text
    • https://marsanz.pl/uploads/fck/file/91321973745.pdfIn PDF document text
    • https://nasikampung.info/contents/files/fenutivixegix.pdfIn PDF document text
    • https://online-wums.com/files/files/tapuvavugakusijawa.pdfIn PDF document text
    • http://gyn-ordi.at/myPix/file/xawelesopokelewebitepi.pdfIn PDF document text
    • http://short-story.ru/upload/file/38563863629.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=easiest+way+to+learn+tensesPDF 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_off0000b152.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB152 14692 bytes
SHA-256: edaf846e5e83d827d0e05ea6d17df3e17b2964b28150527eead2ced87be58d09
font_01_sfnt_off0000d658.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD658 10284 bytes
SHA-256: f84c88017c67cc9b626134e8647830f03c1b0698c200d3a4ea4d142abd6fc00e
font_02_sfnt_off0000edb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDB1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1