Malicious PDF — malware analysis report

Static analysis result for SHA-256 87a4bbf8a1b7cd4a…

MALICIOUS

PDF

88.5 KB Created: 2021-09-11 05:16:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 0e9ee800fe14e8b5741dd6284633cc44 SHA-1: 7d839eea0453dca3fde511569c0165c09b4f819e SHA-256: 87a4bbf8a1b7cd4a8a268081350e9354d02ca945627e8bb60edd03682d65c409
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous embedded URLs that point to various domains, many of which appear to be compromised or disposable hosting. Heuristics indicate this is a link farm designed to redirect users, likely for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

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 https://coretry.ru/uplcv?utm_term=sultan+movie+watching+online PDF link annotation
    • http://hueide.com/upload/files/vogaxuruzuta.pdfIn PDF document text
    • http://joyandwowbook.com/upload/file/bomuwagus.pdfIn PDF document text
    • http://grasslandtj.com/upload/files/47146566259.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/92cd99b08dd42ecef2db42f3aa60a56e/57876800797.pdfIn PDF document text
    • https://doxity.ro/ckfinder/userfiles/files/dedifunipejom.pdfIn PDF document text
    • http://podhoru.cz/userfiles/file/razar.pdfIn PDF document text
    • https://siam-royal-view.ru/data/files/xesap.pdfIn PDF document text
    • http://jatechkj.pl/upload/fck/file/46060292220.pdfIn PDF document text
    • http://hak-al.com/resimler/files/91997486062.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/a06fd7beae84117b62dbe260d17bc1dd/sopubefoz.pdfIn PDF document text
    • https://www.abrasco.org.br/ckfinder/userfiles/files/53160451544.pdfIn PDF document text
    • http://ilkemymm.com/image/files/16826758518.pdfIn PDF document text
    • http://brukikostka.pl/uploads/page/file/18284849711.pdfIn PDF document text
    • http://predit.ru/admin/ckfinder/userfiles/files/14692697101.pdfIn PDF document text
    • http://ristoranteyuri2.com/userfiles/file/51140992593.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1613b302a2222d---fizazurode.pdfIn PDF document text
    • http://ayurveda-shiatsu-nice.com/upload/files/fuzowozuboworakapow.pdfIn PDF document text
    • http://edwardfmcgintypa.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/77089063817.pdfIn PDF document text
    • https://www.shipgo17.com/plugin/ckeditor/ckfinder/userfiles/files/dukurodofukiluvu.pdfIn PDF document text
    • https://eric-parnes.shortex.com/ckfinder/userfiles/files/12549461827.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130f15e7472d---70539885000.pdfIn PDF document text
    • https://mabuksusu2.com/contents/files/96142445730.pdfIn PDF document text
    • http://happysmilecard.com/uploads/files/30305096692.pdfIn PDF document text
    • http://caerulumpharma.com/upload/files/sefulukazedozu.pdfIn PDF document text
    • https://sausalito.com/wysiwygfiles/file/92886402944.pdfIn PDF document text
    • 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_off0000f67e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF67E 10736 bytes
SHA-256: 743921f7d3e4f64e5530c226b7fa0ff3c144300448a628c6eb83e14fc2e03c10
font_01_sfnt_off00010f0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F0C 17596 bytes
SHA-256: 281373f86592c7790220e6fad2a206caa61b8d56e64c3c05fd30edca9cc1f5ad
font_02_sfnt_off00013c4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C4A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1