Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec04c9afc3eba910…

MALICIOUS

PDF

83.8 KB Created: 2021-09-17 18:25:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ab8329ad1c8923e50003e266b18be0fb SHA-1: f628ac7bf4591e4ee7bc47b3a480065b4fd15925 SHA-256: ec04c9afc3eba910eb642b112cf99452742b4c65fc24a739c01a888658dfd710
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous external URIs and is identified as a link farm on disposable hosting, suggesting a lure to external malicious sites. Although no scripts were explicitly extracted, the PDF structure and numerous embedded URLs point towards an attack pattern involving redirection to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://nomylo.ru/uplcv?utm_term=moshi+kotlin+tutorial PDF link annotation
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140ebe5d6105---difixefipenutavelejerebas.pdfIn PDF document text
    • http://tribo.kz/userfiles/File/93077585852.pdfIn PDF document text
    • http://maybaobidinhdinh.com/upload/files/kabisobamemiporubemilexe.pdfIn PDF document text
    • https://ural-aiti.ru/admin/ckfinder/userfiles/files/41246265961.pdfIn PDF document text
    • http://zzzwchem.com/upload/files/zusetodibexogafeteterupeb.pdfIn PDF document text
    • http://fluitec.fr/ressource/site-image/files/17899976207.pdfIn PDF document text
    • http://le-nora.com/userfiles/file/75872527602.pdfIn PDF document text
    • https://eletmodguru.hu/files/files/8737049778.pdfIn PDF document text
    • https://greenlakepaint.com/ckfinder/userfiles/files/6365765376.pdfIn PDF document text
    • http://sosonomo.com/ckfinder/userfiles/files/65607102308.pdfIn PDF document text
    • http://sahrugs.com/userfiles/file/98335439962.pdfIn PDF document text
    • http://www.dogwoodagility.nl/ckfinder/userfiles/files/65373393566.pdfIn PDF document text
    • http://www.mbk-montage.nl/ckfinder/userfiles/files/lazesuxosizawuwafip.pdfIn PDF document text
    • https://ezsprinting.com/userfiles/file/77537811904.pdfIn PDF document text
    • https://apatity.verlauf-ekb.ru/admin/ckfinder/userfiles/files/tewumiwizulapolafo.pdfIn PDF document text
    • https://olterus.net/contents/files/dakemenataxogatavipaxog.pdfIn PDF document text
    • http://erictex.com/ufiles/files/julenabulosidadogakujobu.pdfIn PDF document text
    • http://n3ss.ro/ckfinder/userfiles/files/96406910252.pdfIn PDF document text
    • http://gaziogluenerji.com/images_upload/files/kifil.pdfIn PDF document text
    • https://safe-international.com/userfiles/file/15153759977.pdfIn PDF document text
    • http://geoodwierty.pl/files/file/fazasapegenuvuwazajevigex.pdfIn PDF document text
    • https://beautyyaurient.com/editor_upload/file/gegazajuk.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_off0000e1f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1F6 10260 bytes
SHA-256: cad0a906074f49a6b90ba072379b6d480d55569065a6f22f152d6e1ca6160bde
font_01_sfnt_off0000f8f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8F4 18408 bytes
SHA-256: d28fa21deb5e9da9c6e9440a111826f2d59bf0826712c0b0cf24747cd07bc415
font_02_sfnt_off0001299d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1299D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1