Malicious PDF — malware analysis report

Static analysis result for SHA-256 a39fef026944ae59…

MALICIOUS

PDF

72.6 KB Created: 2021-09-17 22:09:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 4a5ee87179351a2589918d54d576188e SHA-1: b961137aa243e800665a5a17341e13bf1ab6e31a SHA-256: a39fef026944ae59ce49d81db74cb25bb1a4feaf1d4314dafcbad91ba26ae136
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for exploiting PDF vulnerabilities or delivering malicious content. Heuristics indicate it functions as a link farm, directing users to multiple compromised websites, some hosted on disposable domains. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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 https://empresa-venta.hr/files/mikesexinut.pdf In PDF document text
    • http://oiseau-bleu-morzine.com/userfiles/file/tekinubagipomud.pdfIn PDF document text
    • http://reliancefla.com/admin/images/file/kezujuv.pdfIn PDF document text
    • https://www.shamshabaddiocese.org/files/js/ckfinder/userfiles/files/zewafilevipepesukirapo.pdfIn PDF document text
    • http://lecieldesandes.fr/ckfinder/userfiles/files/7651546536.pdfIn PDF document text
    • http://pokwuttibut.com/file_media/file_image/file/timazukulibojajamoko.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/16140bc03df329---refilolinijuxopa.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1613432f446156---22298316461.pdfIn PDF document text
    • http://happinessgown.com/upload/users/files/29869397021.pdfIn PDF document text
    • https://die-elke.de/cms/elke_page_files/file/mafitawujepifa.pdfIn PDF document text
    • https://rowsontw.com/shopadmin/upload/files/85378825192.pdfIn PDF document text
    • http://moneymaker-gold.de/files/kivasokapaneb.pdfIn PDF document text
    • https://hkbca.org/UploadFiles/file/20210910071531107.pdfIn PDF document text
    • http://thunderstar.cn/userfiles/file/20210906153754169320624.pdfIn PDF document text
    • http://sweatrinserepeat.com/ckfinder/userfiles/files/1379753196.pdfIn PDF document text
    • http://www.vandiestbrandstoffen.be/uploads/files/sedilezujuletosijo.pdfIn PDF document text
    • http://com123.vn/uploads/file/joxiluwi.pdfIn PDF document text
    • http://thcscatquea.hoaiduc.edu.vn/ckfinder/userfiles/files/bidugojosonafivuxaro.pdfIn PDF document text
    • http://noahmission.org/dataroom/file/48463579294.pdfIn PDF document text
    • https://refakatci.net/userfiles/file/rojagumozekixewuko.pdfIn PDF document text
    • http://daglichtfilters.nl/ckfinder/userfiles/files/80923457498.pdfIn PDF document text
    • http://montazerangroup.com/uploader/file/64234725515.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1613dce74bf022---73542911897.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=english+grammar+in+use+pre+intermediate+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_off0000b42d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB42D 18076 bytes
SHA-256: 8f0092276e99dfc5079d0b8cb517212694e12063a5a38ded24e6dd58e93861de
font_01_sfnt_off0000e236.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE236 10908 bytes
SHA-256: c3b6f5a7ae3ab46b76a4aa47179b75a35defd632abb70f116a2b6a92bcbfbb9e
font_02_sfnt_off0000fafd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAFD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.