Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8287c97bf1045d0…

MALICIOUS

PDF

71.1 KB Created: 2021-09-18 09:14:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: bdead9d74516bda0f96df97077091e8f SHA-1: 238834d60eb73384902868b0e4eb00908d9144f1 SHA-256: a8287c97bf1045d07ad936884704ef0abfaf94cf2399c8f38b09eb6d90a4b197
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to potentially compromised websites, many of which host other PDF files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of external URI heuristics and link farm patterns suggests an attempt to direct users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/57d26d438ee6a02a3de8ad34bb79027d/55725400448.pdf In PDF document text
    • http://gajagotour.com/UserFiles/file/42944501534.pdfIn PDF document text
    • http://universalestetic.com/userfiles/file/78897796528.pdfIn PDF document text
    • https://thuaphatlaihoanghuy.com/uploads/files/tagixukiviziwavojabunam.pdfIn PDF document text
    • http://willbramephotography.com/wamuselages.pdfIn PDF document text
    • https://premium-house.uz/images/file/11990830863.pdfIn PDF document text
    • http://aygroupmuh.com/image/files/dobokeb.pdfIn PDF document text
    • http://tantusmarina.com/UserFiles/file/42744988015.pdfIn PDF document text
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/2aa53b44ba18b6e44cce8f53dd0387fe/lotofezebej.pdfIn PDF document text
    • http://easytravel63.ru/ckfinder/userfiles/files/32545516043.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a1a9fbe2a2---kosudimumerarimi.pdfIn PDF document text
    • http://giayviettri.com/img-ftec/files/wataval.pdfIn PDF document text
    • http://auksozvynas.lt/userfiles/file/rubopibiwilafiboruxu.pdfIn PDF document text
    • https://insp.biz/img/file/6683357280.pdfIn PDF document text
    • http://gewoongroen.eu/app/webroot/files/userfiles/files/7288316514.pdfIn PDF document text
    • https://motodubai.com/uploaded_images/files/75775710839.pdfIn PDF document text
    • http://avandcie-automation.com/ckfinder/userfiles/files/38697511270.pdfIn PDF document text
    • https://mptradingcompany.com/userfiles/file/73797415356.pdfIn PDF document text
    • http://jonme.net/ckupload/files/namugatuvifumojatakepesif.pdfIn PDF document text
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ca30a1259e---lojomuxewefe.pdfIn PDF document text
    • http://kbautotech.com/board/datafiles/imagefile/mibagofelejerisafulo.pdfIn PDF document text
    • http://lawyermo.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kimezabisomes.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=the+greatest+secret+pdf+free+downloadPDF 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_off0000b542.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB542 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cd54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD54 15772 bytes
SHA-256: cbd8b7feaa6f3259c7c3dfc7d62324876d57cb74322f9ebf6b46f0795674f247
font_02_sfnt_off0000f5b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5B0 10856 bytes
SHA-256: 77e437bf8de463689b7346b50e550d12fef5814d3934f7c92399fa44dfde186a