Malicious PDF — malware analysis report

Static analysis result for SHA-256 c7149e9b4fec87d8…

MALICIOUS

PDF

85.7 KB Created: 2021-09-01 10:21:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: c4866f0eeb7efb090870cc0b36f49761 SHA-1: b7a6a015926966cb778094d17b4b3b8f8003554d SHA-256: c7149e9b4fec87d84284291ba1eb54e2a350810cdac7949cdcb6c85efcb477b2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The PDF contains a link farm directing to numerous URLs, several of which are hosted on compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct content-based clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://thermogroup.ru/uploads/files/30261804664.pdf In PDF document text
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/9op77legsi9lmvda95r3al89jl/xewafuxevabem.pdfIn PDF document text
    • https://binarbaidrealestate.com/public_html/userfiles/file/94226895446.pdfIn PDF document text
    • https://magazinul-de-instalatii-sanitare.ro/app/webroot/files/userfiles/files/xupegugisof.pdfIn PDF document text
    • http://tecsun-moscow.ru/docs/file/lifimuvunaxeloburekitavu.pdfIn PDF document text
    • http://stavo-bazar.cz/userfiles/file/fafevoli.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609e09c462dd8---78385546334.pdfIn PDF document text
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078b021dcd99---kajigabupoj.pdfIn PDF document text
    • http://pcwenhua.com/uploadimg/file/1622795520263554242.pdfIn PDF document text
    • https://www.esfa.bg/root/ckfinder/userfiles/files/gijazagojefi.pdfIn PDF document text
    • http://schodylux.pl/userfiles/file/6810910503.pdfIn PDF document text
    • http://www.ellisrasbetonwerke.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a430d4e172e---4327581527.pdfIn PDF document text
    • http://keitbg.com/images/files/42245455972.pdfIn PDF document text
    • https://tenfci.org/userfiles/file/rozobapekomotugepagikar.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607fd47def09d---58606499323.pdfIn PDF document text
    • http://www.integra-cr.cz/administrace/ckfinder/userfiles/files/86755775508.pdfIn PDF document text
    • http://architettotoma.it/userfiles/files/90489193597.pdfIn PDF document text
    • https://full-flavors.com/img/Data/file/5853144811.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16092cb33f05f2---94769261727.pdfIn PDF document text
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/54c75645b6696e5a098c34233d7094ae/wadunel.pdfIn PDF document text
    • http://vitajeans.com/ckfinder/userfiles/files/97445530905.pdfIn PDF document text
    • http://cedule-plachty.cz/files/file/45511237988.pdfIn PDF document text
    • https://aimara-bg.com/userfiles/file/wupejegupadikof.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=summary+of+the+oval+portrait+by+edgar+allan+poePDF 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_off0000e5f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5F2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fe09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE09 11272 bytes
SHA-256: 2f599f3daa3d0bc07e99a2d1acaacd8ff83965f9bac922ff2bce0ea546f97d80
font_02_sfnt_off000117df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117DF 18328 bytes
SHA-256: 78986af98eb63542a67126182d1da2f37225516f5463b641967e61ddadb3dff0