Malicious PDF — malware analysis report

Static analysis result for SHA-256 dfdf0924f8122818…

MALICIOUS

PDF

84.8 KB Created: 2021-08-16 12:36:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: b15173017d50658a8f62f4d5e07899d8 SHA-1: 7feb7dd4d107862c59d88b0327f2006c4453a057 SHA-256: dfdf0924f8122818cfa06ce0848f961e47b5c2b5b749b54d8a2dca07bf745bdc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple compromised WordPress sites and potentially malicious URLs, likely for phishing or malware distribution. The presence of embedded URLs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic strongly suggest a phishing or scamming operation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://oniceh.ru/uplcv?utm_term=how+to+write+authorization+letter+to+bank+on+behalf PDF link annotation
    • https://mrmusicfoundation.org/wp-content/plugins/super-forms/uploads/php/files/fjgd4ajcskf8r45kbvu7hml009/57121813967.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16086197f61f2f---bimibena.pdfIn PDF document text
    • https://samowar.ch/upload/file/21706879339.pdfIn PDF document text
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/ovmllgkatrehshjjpacn5bsb8n/fusijudubaxijuxizer.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/1607b24d759afa---puripozufinup.pdfIn PDF document text
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d5b01728b47---zadipezegapowu.pdfIn PDF document text
    • https://gradeagroup.com/wp-content/plugins/super-forms/uploads/php/files/u0996j5j1oj81ujb2aa9gn0g1a/gilatemusevo.pdfIn PDF document text
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/h2715pvujvisrqr5okgde6eg2a/47250692705.pdfIn PDF document text
    • https://smartstone.ca/userfiles/files/zatagokedukisugeg.pdfIn PDF document text
    • http://fazekaskozpont.hu/images/upload/file/navamigux.pdfIn PDF document text
    • https://deesudcoolingtower.com/userfiles/file/zunetuzagerepufimij.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/161066c51bc9bf---45899333724.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2a5361424e---34546162311.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16088165c7ccb6---78711747129.pdfIn PDF document text
    • https://khabul.mn/mmpa/userfiles/files/87422095462.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/93d4f1f78956e36954d51620a2c90c09/tukizikakupunogobokosirag.pdfIn PDF document text
    • https://institut-arabe.org/ckfinder/userfiles/files/68304465245.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094101c1b142---puboxidonufuw.pdfIn PDF document text
    • http://ristoranteibucanieri.it/userfiles/files/kixubapukoturera.pdfIn PDF document text
    • https://cr2tek.com/userfiles/Proj_Name//files/zatifenulifukabawo.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/657pl2jf21ph28i26o93709tat/62787042052.pdfIn PDF document text
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092d5eeaece9---73321753769.pdfIn PDF document text
    • https://wheelmartthailand.com/image/upload/File/89263524023.pdfIn PDF document text
    • http://anhuicrew.com/upload_fck/file/2021-5-2/20210502103826710753.pdfIn PDF document text
    • https://moulindelarroque.com/userfiles/file/fuvokikol.pdfIn PDF document text
    • https://agmatbaa.com/upload/files/puzirexitejafozop.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_off0000e801.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE801 10612 bytes
SHA-256: f65045859c0df38b98ebd48c885da3e08a3a48b50a134697c07536017493361b
font_01_sfnt_off00010033.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10033 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011845.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11845 17044 bytes
SHA-256: 9cd94d8e71d15e6b3f52f3c83cf39376c14fb4ecb2f6ef895a112a783b8948d4