Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb3a066ac75df209…

MALICIOUS

PDF

70.0 KB Created: 2021-09-25 01:10:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: c1c8df2b8745460a8e52986cece8c581 SHA-1: fea18c8718b36d6811f79c0a66a5ba6867a766c7 SHA-256: cb3a066ac75df2099ae088ca98b12f1d9c06a03655d93211b168e1b8b196bb9d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous embedded URLs that redirect to various domains, likely for phishing or malware distribution. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, identifying it as a link farm on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://wastran.ru/uplcv?utm_term=most+popular+minecraft+servers PDF link annotation
    • http://moretonassets.net/userfiles/vojimujijanevigijimi.pdfIn PDF document text
    • http://premiumcsp.com/uploads/files/nepidazagobizuruxowepi.pdfIn PDF document text
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613d61e95e254---24008741634.pdfIn PDF document text
    • http://clinicaveterinariagussago.com/userfiles/files/65414531973.pdfIn PDF document text
    • http://gmart-express.com/demo/uploadpic/file/soravamazulopusedad.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/68617972868.pdfIn PDF document text
    • http://chapaconoticias.com/assets/ckfinder/core/connector/php/uploads/files/44550195707.pdfIn PDF document text
    • https://www.hmgfinance.com/ckfinder/userfiles/files/fifevaxemi.pdfIn PDF document text
    • https://ego-sofa.tw/uploads/files/202109191838123034.pdfIn PDF document text
    • http://seoaudytor.pl/userfiles/file/xejigupelewiduwatogexunaf.pdfIn PDF document text
    • https://copacndg.com/images/uploads/files/pufakufulopijusa.pdfIn PDF document text
    • http://avvocatoandreabruschi.it/userfiles/files/pawotuxomiwakewos.pdfIn PDF document text
    • http://mwbright.com/upload_fck/file/2021-9-10/20210910220252404020.pdfIn PDF document text
    • https://5703n1n6999-6a55.com/contents/files/kabixonofigifovefavit.pdfIn PDF document text
    • http://amindoost.ir/images/upload/files/34419650519.pdfIn PDF document text
    • https://www.prshots.com/ckfinder/userfiles/files/14072940837.pdfIn PDF document text
    • http://neza.cz/UserFiles/File/didewagevanugu.pdfIn PDF document text
    • https://www.agencesramos.com/ckfinder/userfiles/files/9582183216.pdfIn PDF document text
    • https://austarpharma.com/upload/files/78042841018.pdfIn PDF document text
    • http://johnmichaelharrisonlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/62688236843.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/1614687ea504f8---gaxekoj.pdfIn PDF document text
    • http://abwmarlboropike.com/uploads/files/34076956184.pdfIn PDF document text
    • http://gtlmarinefuel.com/userfiles/file/putaxovizog.pdfIn PDF document text
    • https://ezsprinting.com/userfiles/file/77537811904.pdfIn PDF document text
    • http://minhquoc.vn/ckfinder/userfiles/files/31324208350.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_off0000b173.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB173 10800 bytes
SHA-256: b121529b6125c4cc3c08fa78d941059d98a460756e7f4ac48d6356c7c021e158
font_01_sfnt_off0000ca69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA69 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e27b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE27B 15788 bytes
SHA-256: 4102c628032be832513c31f88cf8c5ac12f19549c7fc188601cb83e6c6cea7ca