Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a33ab820a9d7ae4…

MALICIOUS

PDF

84.0 KB Created: 2021-09-09 06:11:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4650668a290a726986df90c63528d7c1 SHA-1: 24c84cfcf8a063404010882c2802d3b7fb328158 SHA-256: 9a33ab820a9d7ae4fa8616d9064cfc87ff8838f9fe29bdcda0d884f09c04fcb3
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that form a link farm, a common tactic for phishing or SEO manipulation. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics suggests the document is designed to redirect users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://catamma.ru/uplcv?utm_term=video+star+free+text+qr+codes
    • http://cheumst.com/upload/fckeditor/file/70282697992.pdf
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/cd4dc9ca22f16d6390b2743a7a383499/suvewoku.pdf
    • https://quangcaowebsite.xemlaco.com/uploads/files/54985579851.pdf
    • https://webvitamin.vn/app/webroot/uploads/files/dajulomegowuremeno.pdf
    • https://lentes123.com/aym_image/files/78704128453.pdf
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136f1aac938b---bovob.pdf
    • http://energo-winstal.pl/userfiles/file/rawapide.pdf
    • https://dalycity.com/wysiwygfiles/file/vapigubiwulapajis.pdf
    • http://salwex.hu/file/35612931495.pdf
    • https://ghadir-eng.com/userfiles/files/26031078885.pdf
    • http://sutinlawkrabi.com/ckfinder/userfiles/files/15261070392.pdf
    • https://habibitoursegypt.com/ckfinder/userfiles/files/4006487309.pdf
    • http://ecoaga.com/documentos/file/vunumonafojubawowubugilo.pdf
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/1612eebd3719a0---wisunajixeli.pdf
    • https://www.pension-chevaux-haras-gabereau.fr/ckfinder/userfiles/files/92871325178.pdf
    • http://alt-1c.ru/userfiles/file/setudazelofi.pdf
    • http://frutapac.com/ckfinder/userfiles/files/pajekivutifaleliwafeb.pdf
    • http://silver.jo/ckfinder/blanc/files/49409407927.pdf
    • http://whatcanidoforyou.eu/publish/file/namazezem.pdf
    • http://ballmillfactory.com/d/files/16787911440.pdf
    • http://cnpair.com/userfiles/file/kozasizediwupapu.pdf
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134ea045581e---10726837669.pdf
    • http://wintec-samu.hu/uploads/files/pudivuliwinujenona.pdf
    • http://cuanhuadanang.vn/uploads/image/files/wumorudibixi.pdf
    • 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_off0000e38d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE38D 16792 bytes
font_01_sfnt_off0000fb9f.bin
aa4f271ee98d7f82b7f0b86e62ccd3212f84d445a09d07b504b9ea39efed6d30
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB9F 17744 bytes
font_02_sfnt_off000129eb.bin
d74e01db65506d8a0046e57f96f0329730b2a5f56c31c183f1d28ac543eb0d01
pdf-font-stream PDF embedded font (sfnt) at offset 0x129EB 10536 bytes