Malicious PDF — malware analysis report

Static analysis result for SHA-256 ae887ca50531c51d…

MALICIOUS

PDF

83.4 KB Created: 2021-09-13 02:57:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 8bc43ba42ba7a38399ee4139f5bbfb06 SHA-1: df888ff5ec71cde4ffff5c18a6de89b5872b5e74 SHA-256: ae887ca50531c51d037e94e75ec2bdb9433a948b0302c3797d5aef035b3faa24
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 high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to PDF files hosted on potentially disposable domains, suggesting a link farm or redirection mechanism. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to obscure the final destination. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it is used to redirect users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://plewmal-d.com/Uploads/files/ketorozek.pdf In PDF document text
    • http://tabbanbros.com/admin/fckeditor/editor/filemanager/connectors/upload/file/69224800089.pdfIn PDF document text
    • http://romanasulcikova.cz/userfiles/84819173818.pdfIn PDF document text
    • https://bibliotheque-des-arts.com/ckfinder/userfiles/files/piboninuzopinolunijinipup.pdfIn PDF document text
    • http://k3projekt.pl/uploads/userfiles/files/54798109558.pdfIn PDF document text
    • http://hide-bo.com/img/tmp/file/93002205525.pdfIn PDF document text
    • https://cambodiaangkorhomestay.com/userfiles/file/nijodoxobikiduw.pdfIn PDF document text
    • http://swvocal.com/data/se2/file/65361121828.pdfIn PDF document text
    • http://esen.life/userfiles/file/89102269515.pdfIn PDF document text
    • http://nigerseedindia.com/uploads/35273527108.pdfIn PDF document text
    • http://mecaniquekd.ca/upload/file/32525629430.pdfIn PDF document text
    • http://kopdesign.nl/userfiles/file/lubanutako.pdfIn PDF document text
    • https://kangaroovietuc.vn/webroot/img/files/24460670002.pdfIn PDF document text
    • https://aneri12.cz/res/file/wuset.pdfIn PDF document text
    • http://hotelamadeustorino.com/userfiles/files/44206030683.pdfIn PDF document text
    • http://hockeydh.com/files/ups/files/50667350632.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161342812d07fc---9495321790.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/8b6e2c85611f4baec7daf5f674272766/doniwazavor.pdfIn PDF document text
    • http://l-max.ru/userfiles/file/kudimum.pdfIn PDF document text
    • http://xn--80aadq3ae7aa5k.xn--p1ai/upload/file/55157082533.pdfIn PDF document text
    • http://intertravel.hu/_user/file/gotewejififaber.pdfIn PDF document text
    • https://sanvexe.vn/webroot/img/files/lamafew.pdfIn PDF document text
    • http://sp2wronki.pl/fotki/fotki/file/ziwofupozujejodozowu.pdfIn PDF document text
    • https://hoangvan.vn/wp-content/uploads/files/39763530045.pdfIn PDF document text
    • http://dispensapertutti.com/userfiles/files/17367980236.pdfIn PDF document text
    • https://kisikana.hr/UserFiles/files/25304646872.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=darker+screen+filter+apkPDF 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_off0000e0c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0C4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f8d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8D6 18024 bytes
SHA-256: 5f459447daf0906052bda0e6c57f2fb3bd0a298019f2834bcb23f18f9cd9d275
font_02_sfnt_off000127c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127C8 10444 bytes
SHA-256: 7763f520ed7a9d700563ae397e5f9ed9eaf1ed875fd32a3c7041b18d246662b9