Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6ff429c2ad7d5ab…

MALICIOUS

PDF

76.3 KB Created: 2021-09-08 13:52:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: f9fafd33a6c521d82ccbba91d46bd25e SHA-1: e6a67136a738fa099f39c89a03bc343549584ecb SHA-256: a6ff429c2ad7d5abd5e0ea5df8b9455fab2b7ecb03af6b690b1ad6052ab7430a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and link farm behavior are consistent with techniques used to host malicious content or redirect to phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://crysiq.ru/uplcv?utm_term=auto+mechanics+book+pdf PDF link annotation
    • https://terminarz.online/kosmetyczka/krakow/files/loduwetiwiwojenuzalidixi.pdfIn PDF document text
    • https://ohcsi.com/ckfinder/userfiles/files/feguverinelafov.pdfIn PDF document text
    • http://beming.com/ressource/site-image/files/40846891382.pdfIn PDF document text
    • https://larioenergy.net/uploads/file/wijejod.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/16136121da8b97---48902441150.pdfIn PDF document text
    • http://eco-building.cz/UserFiles/File/zuxoposa.pdfIn PDF document text
    • https://discovercefalu.com/_data/images/file/94137444830.pdfIn PDF document text
    • http://kemmurad.com/webroot/img/files/89571644905.pdfIn PDF document text
    • http://www.anjhimayath.com/upload/file/donefagifosukiviton.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613147decc011---fevimun.pdfIn PDF document text
    • https://hw-power.com/uploads/ckfiles/files/6137dde4e0375.pdfIn PDF document text
    • http://screen.by/images/file/mekafuweb.pdfIn PDF document text
    • https://implantsdentairesdesmoulins.com/upload/editor/file/23176157966.pdfIn PDF document text
    • http://sentralperdana.com/file/linidatukiridin.pdfIn PDF document text
    • http://abwsalisbury.com/uploads/files/8468252877.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613253c3ae579---44846659814.pdfIn PDF document text
    • https://duocvinhkim.com/userfiles/file/dodisetuvupeged.pdfIn PDF document text
    • https://probidjp.com/ckfinder/userfiles/files/20210906_115743.pdfIn PDF document text
    • http://ivankrivanek.com/userfiles/file/80639692699.pdfIn PDF document text
    • http://andreaslasnik.com/data/files/34845052086.pdfIn PDF document text
    • http://teplorium.su/userfiles/file/32741894593.pdfIn PDF document text
    • http://tuttotop.com/userfiles/files/napijitiwezadoj.pdfIn PDF document text
    • http://tochuchoinghi.org/files/98693896446.pdfIn PDF document text
    • https://e-ssuances.com/ckfinder/userfiles/files/kunob.pdfIn PDF document text
    • 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_off0000c8a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8A0 11052 bytes
SHA-256: bc016a10d6076c1c42468d67640a8a1cdae0e4ae5a553d872145dbb0b8f4c838
font_01_sfnt_off0000e1fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1FD 16152 bytes
SHA-256: 7a82eac9daea0b982ea2f4bef6cea2990f39e193dc660198e0b49880e6feeb02
font_02_sfnt_off00010b84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B84 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1