Malicious PDF — malware analysis report

Static analysis result for SHA-256 273ba790d6eff802…

MALICIOUS

PDF

81.6 KB Created: 2021-09-03 15:55:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 45104951127e339e24104ce2922c7f9d SHA-1: cbecae0953e5334807e377dea8ff47d49c99d779 SHA-256: 273ba790d6eff80210b04414b4570423a6a8e411d1acf282ca72a4710d3148c1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF contains embedded JavaScript, which is a common technique for exploiting PDF vulnerabilities or redirecting users to malicious sites. The numerous external URIs, many hosted on compromised or disposable domains, suggest a link farm designed to obscure the ultimate destination, likely a phishing page or malware download. The ClamAV detection and ML classifier strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://langeline.com/ckeditor/upload/files/fekoge.pdf
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0b3dcd703a---murarijopolepimavexe.pdf
    • http://cokhixnktientien.com/Images_upload/files/44573325377.pdf
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1607bddf958fa5---86898034930.pdf
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/160ac3c6e6da5f---22458656460.pdf
    • https://milorem-service.ru/userfiles/file/xubidofemerun.pdf
    • http://miet-boot.ch/images/uploadedimages/file/fajuxuwalaxebedebibabanes.pdf
    • http://alnoorcity.com/userfiles/file/2469926102.pdf
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/160826ea4e0ae1---92289087549.pdf
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ab84c0f2c3---nozabokupukadiwafu.pdf
    • http://www.feniuniversity.edu.bd/app/webroot/ckfinder/userfiles/files/91184723570.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae9a69d1482---8418292066.pdf
    • http://jshtextile.com/UserFiles/file///nibev.pdf
    • https://rewaqousha.net/userfiles/files/wenaboxewudam.pdf
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae7eacc3e07---64864916094.pdf
    • http://gok-maciejowice.pl/js/ckfinder/userfiles/files/19646112640.pdf
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16131564839892---20519351765.pdf
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/n7cc0u3tnavc38rfv5h3ol0ad3/nizefafadevedufuz.pdf
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/cff21d40547fa343e6ca8e844d7bf4d9/11691217623.pdf
    • http://www.ctnphrae.com/ckfinder/userfiles/files/fimovukojafo.pdf
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16088005089338---sitemijokukenidezifakuv.pdf
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16115a63ca1347---63686976276.pdf
    • http://laduses.nl/image/file/xuwulolusaterike.pdf
    • http://studiotecnicoprato.eu/userfiles/files/39271140429.pdf
    • http://www.siscbolivia.com/admin/uploaded/fck/file/terusakegu.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=drill+bit+size+chart+for+taps+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_off0000dafd.bin
6aac4775b320f28455f1be3b4f8d3e714342bf7d349cfb0d7b3839dd486dfb40
pdf-font-stream PDF embedded font (sfnt) at offset 0xDAFD 10816 bytes
font_01_sfnt_off0000f3e6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF3E6 16792 bytes
font_02_sfnt_off00010bf8.bin
bd4fd61f8b382c14859a36186ad3bcadb25382d162dac0ea1646087bf0498089
pdf-font-stream PDF embedded font (sfnt) at offset 0x10BF8 17476 bytes