Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b11c7f4c70a2c86…

MALICIOUS

PDF

90.2 KB Created: 2021-07-09 19:16:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: cdc943d1040c21d92cd457163d2061c2 SHA-1: 379ad20755c5a2f17c3abd5c0fed23cf7d048e60 SHA-256: 6b11c7f4c70a2c86134da79db2204009eb7262939692311bec855332ab01944b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous links to external resources, many hosted on compromised websites, suggesting it functions as a link farm or part of a phishing campaign. The presence of invoice-related language further supports a lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://flyags.com/editorResources/file///nifubadibarujudelilenuba.pdf In PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ed3fdaef6c.pdfIn PDF document text
    • http://bajcsidavidfoto.com/_user/file/zufatanumepulitedisixiki.pdfIn PDF document text
    • https://karapinarinsaat.net/userfiles/upload/file/gupabuxezipobogafubow.pdfIn PDF document text
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/sji2mblntqnf9t8t9mjk7l12ej/jujepejawerusegedemena.pdfIn PDF document text
    • http://dxczx.com/ckfinder/userfiles/files/20210617_151958.pdfIn PDF document text
    • http://biotop-zamosc.pl/userfiles/file/83850544624.pdfIn PDF document text
    • http://tecresconsolidamentorestauro.it/fck_data/file/58058727262.pdfIn PDF document text
    • https://regeneracion-capilar.com/wp-content/plugins/super-forms/uploads/php/files/2c04a0dffc22312b35128e23755c79a2/vunomasovato.pdfIn PDF document text
    • https://bda.ch/ckfinder/userfiles/files/dozup.pdfIn PDF document text
    • https://zlatartopalovic.rs//files/47983596849.pdfIn PDF document text
    • http://kasaitogo.com/uploads/files/9022613234.pdfIn PDF document text
    • http://harc-ias.vn/Images_upload/files/wakuboladasugukajof.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a67258df4f6---89659888870.pdfIn PDF document text
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080603d5d4b6---73833743867.pdfIn PDF document text
    • http://st-communications.com/ckfinder/userfiles/files/wapededigodineb.pdfIn PDF document text
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608528d5d5788---62428239433.pdfIn PDF document text
    • https://calmoinc.com/upload/editor/file/69468525478.pdfIn PDF document text
    • http://aquatherm-graz.at/files/71697320554.pdfIn PDF document text
    • http://ural-kip.ru/admin/ckfinder/userfiles/files/lipuxazobelumijimu.pdfIn PDF document text
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/86us26bfgro35f7bnvtipaj0ul/fomekid.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9f01fb540f---42503851465.pdfIn PDF document text
    • http://jagodkaprzedszkole.pl/userfiles/file/82392351255.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=freelancer+exams+answersPDF 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_off0000fd7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD7B 10244 bytes
SHA-256: f4ca8fedcf98b40b7a8a472aea35821a27baac28b74c6efd94e02facaa199880
font_01_sfnt_off00011482.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11482 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012c94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C94 17868 bytes
SHA-256: e98071e3f1a2dab89756d88410031d6c0b66600438aff6d708fceb451cd6b610