Malicious PDF — malware analysis report

Static analysis result for SHA-256 805b57ec3dfe73b3…

MALICIOUS

PDF

82.6 KB Created: 2021-08-17 03:17:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 70d9274cebabc8e1fa30748462f0d53b SHA-1: 9c5bb3005366af0d8e3169e3f262b2233e5c8b42 SHA-256: 805b57ec3dfe73b377648e8bd5f8d7903d20d1207b47df766bd0cd6f5e11e06c
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the PDF structure itself facilitates the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://condicionamentofisico.com/arquivos/file/87151523346.pdf
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160e27fb06141c---rapona.pdf
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8921f8fa85---54504207231.pdf
    • http://www.teeintact.com/admin/fckeditor/editor/filemanager/connectors/php/img/file/20677849506.pdf
    • http://refah4ter.info/basefile/hotelrefah4terir/files/kusofuwoxuwaxipugubenekaz.pdf
    • http://benefielddarrenfordhicksunited.com/clients/2/21/2186b72972973349411f8b90e6071e14/File/66514226248.pdf
    • http://szao-spb.ru/images/news/file/34657970342.pdf
    • http://www.redactordecontenidos.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160cfc851f22fb---sugiwezototojufezada.pdf
    • https://www.hausbootgeiseltalsee.de/wp-content/plugins/super-forms/uploads/php/files/jp2gqn492hcqqhe35ph43ejhci/57919685527.pdf
    • https://cengilli.com/icerik_images/file/6126928911.pdf
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085e0bb265f6---6981556185.pdf
    • https://bititechnika.com/uploads/file/simabe.pdf
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/ea75bd7bf508435e7396d678b312cb65/85416930861.pdf
    • https://www.libyamonitor.com/sites/all/libraries/ckfinder/userfiles/files/74066896571.pdf
    • https://deycaterers.com/ckfinder/userfiles/files/40594001588.pdf
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608b8f272d4db---60928432889.pdf
    • http://bhhangkhong.com/upload/images/files/19055643140.pdf
    • http://xn--80aadq3ae7aa5k.xn--p1ai/upload/file/gedipefasefarokel.pdf
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/6apligssojt24auo8u5i8d0fhe/tevebuzudulesolu.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611afc125754e---lulubegukagupuwemaxo.pdf
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160e18450a0c20---59440882617.pdf
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16112241989153---83495522957.pdf
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/16086ff466806f---tetifenebofewiwawozud.pdf
    • https://porterbrothersltd.com/app/webroot/uploads/lurulemaxosibe.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=how+to+connect+directv+remote+to+samsung+smart+tv
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000de11.bin
8d851b7d95c9060a3a1ed848e5a5b5b2c1dbe3a89b9bc9f7268f5307641be296
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE11 10912 bytes
font_01_sfnt_off0000f720.bin
f6c46e3b571fc3604518da1461502e30d8fa063d78be867dc4a51ae32707329e
pdf-font-stream PDF embedded font (sfnt) at offset 0xF720 17168 bytes
font_02_sfnt_off000123b8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x123B8 16792 bytes