Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b1ee403cf486898…

MALICIOUS

PDF

74.9 KB Created: 2021-09-01 12:22:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 2e1d7800703d78924d054698ff422b5b SHA-1: 2c948a001e39d5459a709dc8e299f21f72670f1c SHA-256: 8b1ee403cf4868981a034d449ec428538b29e49c411c2eca18640483771131ff
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery through these links. The document body is heavily obfuscated and does not provide direct textual clues, but the heuristic firings and URL analysis confirm its role as a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9919

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://wastran.ru/uplcv?utm_term=monomers+that+make+up+dna+and+rna PDF link annotation
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160e5fd757114d---8310849165.pdfIn PDF document text
    • https://businesslife.com/content/file/wakolaxelefumidobesumuf.pdfIn PDF document text
    • http://art-ball.net/files/file/55893652591.pdfIn PDF document text
    • http://nguyenthaotech.com/upload/files/93401619997.pdfIn PDF document text
    • https://www.marjojaspers.nl/ckfinder/userfiles/files/guzadelanume.pdfIn PDF document text
    • http://grupophi.es/uploads/files/mifufuxakakipijorazuda.pdfIn PDF document text
    • https://zemiigori.com/uploads/file/1293773116.pdfIn PDF document text
    • https://felix-schulze.biz/wp-content/plugins/super-forms/uploads/php/files/sprn4tpbail2rsp6inf3dli1tb/11142520267.pdfIn PDF document text
    • http://cartopack.com/Images/file/57498781928.pdfIn PDF document text
    • https://datawire.gr/files/files/34253524558.pdfIn PDF document text
    • http://ellenia3.eu/userfiles/files/2578984889.pdfIn PDF document text
    • https://www.displaysdirectaustralia.com.au/application/third_party/ckfinder/userfiles/files/16120729280.pdfIn PDF document text
    • https://longhoang.vn/upload/files/zapil.pdfIn PDF document text
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/913274cd0f0fb804a6c9b7d22e3b2fe9/zabugeroza.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/160c40d3beb9cc---18418539921.pdfIn PDF document text
    • http://pk.mo/userfiles/file/mezabobivopujutamopu.pdfIn PDF document text
    • https://fibra-optica.ro/ckfinder/userfiles/files/nuriva.pdfIn PDF document text
    • https://techielingo.com/fck_uploads/files/26275747425.pdfIn PDF document text
    • https://bacninhonline.com/webroot/img/files/nesadofosamugodirositume.pdfIn PDF document text
    • http://ehomeforeclosure.org/images/file/77918838915.pdfIn PDF document text
    • https://pelicanfinancialnetwork.com/ckfinder/userfiles/files/13038220087.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1606d30a19a5d9---fijaxigixiv.pdfIn PDF document text
    • http://actybrain-consult.com/Upload/files/83155620515.pdfIn PDF document text
    • http://yesilderecine.com/admin/editor_resim/file/93097729030.pdfIn PDF document text
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c87c97093c---vurelozurizewaduwoneta.pdfIn PDF document text
    • https://contabil-fiscal.ro/mm/file/kimunizekelawuvo.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_off0000c0ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0AD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d8c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8C4 10704 bytes
SHA-256: b4a13fe5656382aad32961462de23d7963c71a9224e9881afd13c81080f8a5bd
font_02_sfnt_off0000f121.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF121 16672 bytes
SHA-256: 25f52a99e7077abbab5bd7817b6e654465645b4d960d95b3a675f54aed1e4aa1