Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a435ad3b866c66c…

MALICIOUS

PDF

94.7 KB Created: 2021-07-14 10:03:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 662329b2c0d90c14f969c25cc270d483 SHA-1: 09f3cf6349134babc52ceb371065d208e1c88412 SHA-256: 7a435ad3b866c66cafb348da103d08c932d6c176141028e372ccc934b7230e17
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, indicating a link farm designed to distribute traffic. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. The file's structure and numerous external links align with techniques used to obscure the true destination and evade initial detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9918

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/62a261659980c4a2b6a706e1a5abe5e6/zisezo.pdf In PDF document text
    • https://vestol.bg/files/file/57218998714.pdfIn PDF document text
    • https://cicadit.ro/UserFiles/file/vosetizovuzibogizinibum.pdfIn PDF document text
    • http://designpavelzapletal.cz/files/file/47751625541.pdfIn PDF document text
    • http://spiregene.com/image/files/20210714_002654.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083256637fbd---20473981084.pdfIn PDF document text
    • https://signika.pl/Upload/file/jawatabowapulewe.pdfIn PDF document text
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b65b2980390---resibotesipovibifekopexif.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae1d454d8bf---biwekuvuwirobikusolowiwef.pdfIn PDF document text
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160c770d05abbf---73099205658.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/51681659055.pdfIn PDF document text
    • http://macap.nl/app/webroot/files/userfiles/files/kujopuledinovigeradu.pdfIn PDF document text
    • http://ambulatorioveterinariorigolon.eu/userfiles/files/tuwuvap.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/bkktsreib2savkuvdu8qkuqu1p/66107341718.pdfIn PDF document text
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/b6c5e5ed4ec4709cee06b4f56d1f5d89/zegajuso.pdfIn PDF document text
    • https://bomnuocebara.com/quangbasanpham/app/webroot/upload/image/files/86259915734.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608aaeeab8779---webaganupotagalureka.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abe549979c5---kokaxufew.pdfIn PDF document text
    • http://gtshotel.it/images/file/29903754108.pdfIn PDF document text
    • https://umutisi.com/umut/upload/files/85977320851.pdfIn PDF document text
    • http://sme1970reunion.com/clients/7/78/786f1e38e9ed540b4a7d4f5dbcc09398/File/silowemubaxageser.pdfIn PDF document text
    • https://argentinaproduct.com/ckfinder/userfiles/files/vixapoziwuvorez.pdfIn PDF document text
    • https://led7.ru/file/25450619154.pdfIn PDF document text
    • http://c2r-auto.com/uploadfiles/file/2021070403434973499.pdfIn PDF document text
    • https://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/e8fbc6dcf61653c118204e11ae8ffe5d/4970245629.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=pronounce+meaning+in+malayPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f605.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF605 16132 bytes
SHA-256: eb83fb48a2f60ac59fad768156047f025764cad4052c8f34695a9c8dd2456ad8
font_01_sfnt_off00010b72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B72 19412 bytes
SHA-256: 5d8bea68ebe81cb1f5ab95a673318cb349309efb820b8e25ee887aeca1f40358
font_02_sfnt_off00013dc0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13DC0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off000155d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x155D7 10520 bytes
SHA-256: 862eebc32d06fdb9974afa1476f2a1ed3a84ec7ce20a31147d54220d8778facb