Malicious PDF — malware analysis report

Static analysis result for SHA-256 918b633b92e3362f…

MALICIOUS

PDF

91.8 KB Created: 2021-08-26 15:02:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 20cdb9bc4b6c0195c898f7e1d848a1b7 SHA-1: ece507ab8cc8768e3d2b2bcc1d13fa4d74e04a6a SHA-256: 918b633b92e3362f050329f3993861265c74aabf78b4eeda8b1109a71e1cdcff
156 Risk Score

Malware Insights

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

This PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of external links, many pointing to compromised WordPress sites and disposable domains, suggesting a link farm for SEO manipulation or to host phishing content. The document body is unreadable, but the heuristics indicate a malicious intent through its link distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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 http://moiarchitekci.pl/pliki/file/ramibijelevoga.pdf In PDF document text
    • https://cafesca.mx/ckfinder/userfiles/files/neketekoboso.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/8a8ea5840cd5852b1fa908774b25f765/19467335885.pdfIn PDF document text
    • http://bostonmentors.com/userfiles/file/suzoxotitifozutevadadapob.pdfIn PDF document text
    • http://alituncer.com/userfiles/file/71943603486.pdfIn PDF document text
    • https://privatecambodiatour.com/userfiles/file/gufejebotis.pdfIn PDF document text
    • https://www.elitelawnsolutions.co.uk/wp-content/plugins/super-forms/uploads/php/files/p1etif9hob8ajtn1gust6k97jl/63063005949.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/8ea51618dce75943c7d84f8b60339dfc/femuvukumorikak.pdfIn PDF document text
    • https://fotobolfestmeny.hu/mvc/userfiles/file/90373835474.pdfIn PDF document text
    • http://autosklo.sk/pictures/file/kajizaga.pdfIn PDF document text
    • http://qzgj.cn/upload/file/22962791013.pdfIn PDF document text
    • https://atraba-holding.com/userfiles/file/muvalogamibavuneronirup.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160c6b80a933eb---98543761563.pdfIn PDF document text
    • https://www.escon.it/wp-content/plugins/super-forms/uploads/php/files/31751a2d47983549a71f2d473bb6de48/bulefid.pdfIn PDF document text
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/9aq2stroidha78vp6g72gutvca/67009984495.pdfIn PDF document text
    • http://onmamtour.com/FileData/ckfinder/files/20210812_ED14DD325AEB2D5D.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/16076317adf5e4---658992775.pdfIn PDF document text
    • https://sindonis.com/userfiles/file/dubopu.pdfIn PDF document text
    • http://shiksha24.com/userfiles/files/17844506671.pdfIn PDF document text
    • http://seksdagen.nl/userfiles/file/gonepipododopamazeber.pdfIn PDF document text
    • http://dungcumaymoc.com/Images_upload/files/xepisaromaxitusamaxitoxe.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7a30cea839---kijewijufeviw.pdfIn PDF document text
    • https://bunyaminerdemir.com/resimler/files/ziketidupaz.pdfIn PDF document text
    • https://eandjfamilyhealthcenter.com/wp-content/plugins/super-forms/uploads/php/files/2c48c1745c59010fb8d63ff04b0f9ebd/jowogajavujuxenorokisigul.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=advantages+and+disadvantages+of+globalisation+pdfPDF 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_off00010491.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10491 16996 bytes
SHA-256: 3133e0d2aea3658e5bd04398c81c47c16831bd1af524737c83d600e86683a60b
font_01_sfnt_off000130c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130C2 10760 bytes
SHA-256: 93438badcf457783bee3abf6a69eb53ebf0eada40eca25b08873e32b1f2967f0
font_02_sfnt_off00014945.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14945 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1