Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9caf205b3d7f601…

MALICIOUS

PDF

87.1 KB Created: 2021-08-19 02:07:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 3a5fd96059c9130583fa2a3088072db6 SHA-1: f1c8bdfcfed0d1042be8faca24b6a1900c19193f SHA-256: a9caf205b3d7f601e2a8ba8c3e6364cc996ccf9c9b44a0a41ec4c83a9ca189e9
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of links, many pointing to compromised or disposable domains, indicating a link farm or SEO poisoning attempt. The ML classifier also flagged this PDF as malicious with high confidence. While no scripts were extracted, the structure and URL distribution strongly suggest a malicious intent to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 5

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/gqeklta6q2hl9goooep7jo3a67/3275454555.pdf In PDF document text
    • https://fultoys.com/userfiles/62067295771.pdfIn PDF document text
    • https://jeneifogaszat.hu/cikkdata/files/24336618291.pdfIn PDF document text
    • https://absoluteanytime.com/media_file/files/files/43797560111.pdfIn PDF document text
    • http://flirdining.com/uploads/files/2761553672.pdfIn PDF document text
    • http://pekingtogo.com/uploads/files/4310724070.pdfIn PDF document text
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/fbh4326pu682gbkf1h3ljmio00/69508387264.pdfIn PDF document text
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/845354idc474p4tp7iobd5hi23/sozideput.pdfIn PDF document text
    • http://esoftland.com/userfiles/file/59529909923.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606caab4f18e7---99110087900.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b70b1c4806e---62617549100.pdfIn PDF document text
    • https://stiff.pl/ckfinder/userfiles/files/20181184520.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/29c3d40ff91b4f0061828dedf25ae87a/zupapuzodakokak.pdfIn PDF document text
    • http://baodieptailor.com/uploads/2021-07-13/images/files/kotamemuniwuru.pdfIn PDF document text
    • http://mistralizmiryonetim.com/uploads/file/88074799274.pdfIn PDF document text
    • http://svatba-emi.com/uploads/pages/files/46033288622.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a2655d66b71---doganikit.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/45873590812.pdfIn PDF document text
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3aaba93e3---tuwimebexaloxafomag.pdfIn PDF document text
    • http://ottotech.center/userfiles/file/99175149637.pdfIn PDF document text
    • https://www.vedaaz.com/wp-content/plugins/super-forms/uploads/php/files/9db054aaf0ecb1fc0376fbc08513115a/nigigabipajovogosokasijad.pdfIn PDF document text
    • http://kencert.vn/uploads/image/files/34395292803.pdfIn PDF document text
    • https://knurussian.kr/DATA/upload/files/202107061616336126.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=naruto+shippuden+ultimate+ninja+storm+4+character+modsPDF 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_off0000ee7a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE7A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010691.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10691 11064 bytes
SHA-256: 755132b710b45f6e3c9350cfde59c97a5280c22c92af36c25da82fbdaf53d77f
font_02_sfnt_off00012029.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12029 18636 bytes
SHA-256: 991f8016874550525d6a58a025f9ee61478c426ac2b9f0014db1a8ece7f19e53