Malicious PDF — malware analysis report

Static analysis result for SHA-256 9681dc40ce8032a5…

MALICIOUS

PDF

69.1 KB Created: 2021-10-01 12:43:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 94abb856c1c318fb700c1a1d6b4a4171 SHA-1: 62c419a6c6288a59ac5e3ea3c182e488e8856d71 SHA-256: 9681dc40ce8032a535c38f2e5e3d3d290fbd5531368f8bc23ca7d9b566378997
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF document was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic and the presence of numerous embedded URLs suggest the document functions as a link farm, directing users to potentially malicious external sites. The `utm_term` parameter in one of the URLs indicates a potential phishing or download lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://www.dr.schure.net/ckfinder/userfiles/files/kowagajadapada.pdf In PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613730b6f3899---42505331226.pdfIn PDF document text
    • http://vipdiler.ru/files/file/vexideribiwe.pdfIn PDF document text
    • http://vitalchurchesinstitute.com/files/file/63749721750.pdfIn PDF document text
    • http://nhatminhtrading.vn/app/webroot/uploads/files/piloxubegazakisujeket.pdfIn PDF document text
    • http://seasonsblinds.com/uploads/ckfinder/userfiles/files/80349832542.pdfIn PDF document text
    • http://wuchem.com/upload/files/92667574884.pdfIn PDF document text
    • http://icloudcleaners.com/uploads/account/autoresponderfiles/wiwesanefido.pdfIn PDF document text
    • http://currycornersugarland.com/admin/images/file/zagemixixaxujexosu.pdfIn PDF document text
    • http://dunakeszi.varosom.hu/userfiles/files/bipilikol.pdfIn PDF document text
    • https://simbotour.ro/ckfinder/userfiles/files/lawipudabizu.pdfIn PDF document text
    • http://epplast.com/files/file/tazabiwavebulobinuweji.pdfIn PDF document text
    • http://thcsducthang.pgdbactuliem.edu.vn/ckfinder/userfiles/files/39783499028.pdfIn PDF document text
    • http://master-sign.ru/ckfinder/userfiles/files/jedapenagi.pdfIn PDF document text
    • https://lecormier-menuiserie.com/www/upload/files/13129624268.pdfIn PDF document text
    • https://akconta.com/uploads/files/51624241511.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16135307524298---tobumolugosuz.pdfIn PDF document text
    • https://doctmcooper.com/userfiles/files/revezavikuvaxezujezo.pdfIn PDF document text
    • http://salman-is.com/userfiles/file/venigud.pdfIn PDF document text
    • http://phutungotodungha.com/img/files/guzobemipuvep.pdfIn PDF document text
    • https://ladachess.ru/userfiles/file/67133244249.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=case+animatronics+download+androidPDF 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_off0000b040.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB040 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c852.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC852 15008 bytes
SHA-256: 61c9ca66f60b0e7ace3c9ce6e88f5412160802488ec899df701ade18bd3710b3
font_02_sfnt_off0000ee43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE43 10648 bytes
SHA-256: 50770cdd744e631e3a0521558ec3606f5d465d5be906dd48844474e537d61700