Malicious PDF — malware analysis report

Static analysis result for SHA-256 939584d7794798c8…

MALICIOUS

PDF

84.2 KB Created: 2021-09-16 21:12:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 6d1f223617d54300f1486e0e893cc78c SHA-1: 678ba479cb8256518cbdd085c0de57aa0c53191f SHA-256: 939584d7794798c8817553830189e3d780d5f9034c57b6a7312f9b413478e8ca
126 Risk Score

Malware Insights

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

The sample was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV detection as a phishing trojan. The PDF contains numerous external links, many pointing to disposable domains, suggesting a link farm or redirection mechanism. While no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of an attempt to redirect the user to malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://xyoaa.org/sites/default/files/files/zunuvowugamarelen.pdf In PDF document text
    • https://merohamro.com/ckfinder/userfiles/files/gemopijugeromuzafigumis.pdfIn PDF document text
    • http://zamokugrofa.sk/admin/fckeditor/file/49803339434.pdfIn PDF document text
    • http://geoscan.it/userfiles/files/8553776806.pdfIn PDF document text
    • http://asja.ua/userfiles/file/63306910746.pdfIn PDF document text
    • https://www.frontiermyanmar.com/sites/all/libraries/ckfinder/userfiles/files/vekefemimijerunufudugofa.pdfIn PDF document text
    • https://gkscam.com/userfiles/file/55806834191.pdfIn PDF document text
    • http://emilybarnes.com/DEVELOPMENT/VERSIONED/emilybarnes/trunk/sites/default/files/file/kalamarotoritorakifagoni.pdfIn PDF document text
    • https://studybrilliant.online/app/webroot/img/userfiles/file/73465156475.pdfIn PDF document text
    • http://huntland.hu/upload/file/50911915143.pdfIn PDF document text
    • http://ceramicaartisticamarsalese.it/userfiles/files/80140952253.pdfIn PDF document text
    • http://seanbittinger.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/44567137473.pdfIn PDF document text
    • http://donghobaoan.com/uploads/files/misabob.pdfIn PDF document text
    • https://toskov-yordanov.com/userfiles/file/70547661722.pdfIn PDF document text
    • http://cecev.com/stockages/files/93942782082.pdfIn PDF document text
    • http://xn--zb0bw3kv4s8mn.com/upload/fckeditor/file/sukewibelebefegotetevera.pdfIn PDF document text
    • http://remont-etalon.ru/upload/files/70599580298.pdfIn PDF document text
    • http://administratieindex.nl/images/uploads/60972157345.pdfIn PDF document text
    • http://patanamachine.com/imgUpload/files/47208678506.pdfIn PDF document text
    • https://xn--80apefbdm9ah5g.xn--p1ai/userfiles/fotenokuvilesulu.pdfIn PDF document text
    • http://p-jtech.com/userData/board/file/petilujela.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16130ae5d1a075---24959821972.pdfIn PDF document text
    • http://mrcookie.tw/upload/editor/file/051759479005.pdfIn PDF document text
    • http://felixefontesadvogados.com.br/ckfinder/userfiles/files/neretikobazogugowat.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=como+formatear+una+tablet+samsung+galaxy+tab+4PDF 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_off0000e25b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE25B 18168 bytes
SHA-256: b2efc9d20623e9bbafbf81920c808d130d13c3c6931b454f9757b8bf7e9d5126
font_01_sfnt_off00011107.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11107 11028 bytes
SHA-256: 201569569a9bf2ee3819af4e9ef3d1038429306b1950275e6c4159a30d2a4c87
font_02_sfnt_off00012adc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12ADC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1