Malicious PDF — malware analysis report

Static analysis result for SHA-256 19146216e491c0b4…

MALICIOUS

PDF

93.6 KB Created: 2021-08-08 06:22:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 9507ff8ad9828e627cdc02e38b0eb5ce SHA-1: 62b160cdc1f9e05bb67d01f8a4b7922dbea22d17 SHA-256: 19146216e491c0b451acead03bc699bbb102377393f5561fb75df35daea3454a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF that contains numerous embedded URLs, many of which point to compromised WordPress sites hosting PDF files. The ML classifier and ClamAV detection strongly indicate maliciousness. The presence of these links suggests a phishing or malware distribution scheme, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609c30758821f---femokajejoseguzolan.pdf In PDF document text
    • http://centralgiving.com/media/userfiles/file/45273453002.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c8eb8be2e07---rogowevixanimusufas.pdfIn PDF document text
    • https://fo-prefectures.com/pages/files/17545627400.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d7beec5b822---32854645865.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/160da9d91c35fb---notuwokumupusemu.pdfIn PDF document text
    • https://projetounificado.com/uploads/files/jupanoluvujogaxegiz.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/1608fce3cbf1d6---68772412068.pdfIn PDF document text
    • http://vendsol.com/userfiles/file/lozanosemotejetinaxi.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c2fc5404fc0---tetomorotokavamuje.pdfIn PDF document text
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c9c59d5de5---48834954701.pdfIn PDF document text
    • http://tktravel.shop/FileData/ckfinder/files/20210605_78A76A6B7F1BA58E.pdfIn PDF document text
    • https://nolimitscenter.be/peausitive/images/FCKeditor/file/46696650245.pdfIn PDF document text
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/27f7834b4df0bce56c5e499edce9766a/bozadikiwovorurazo.pdfIn PDF document text
    • https://bowenpainter.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b7d41a260d---gusekojutakinav.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1610478c765eae---41189385893.pdfIn PDF document text
    • http://agiusfuneraldirectors.com/files/file/99947936713.pdfIn PDF document text
    • https://hanyauntuktesting.com/contents//files/wufekixunar.pdfIn PDF document text
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/87dd70c8fcd75c7a1ceb0e36265acc61/gojirowo.pdfIn PDF document text
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b25ad00df72---25542688653.pdfIn PDF document text
    • http://bennyhigh73.com/clients/3/33/33ce00c6a031cf3b17a3dcf69aaa7594/File/66926522459.pdfIn PDF document text
    • http://fujiya-la.com/uploads/files/bugabe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=mcgraw+hill+reading+wonders+grade+4+unit+4+teacher%27s+edition+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_off000106e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106E3 17856 bytes
SHA-256: 3d690a2096c627f59d6ffeb7d51b8f011132da100a81ddf2a092637d1739e1f2
font_01_sfnt_off000135dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014df4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14DF4 11192 bytes
SHA-256: 8fe0f48df36ecd4cdd5a534c2d22644e45959655efa9721ae18e833ae717731d