Malicious PDF — malware analysis report

Static analysis result for SHA-256 b427a8349e7783eb…

MALICIOUS

PDF

107.0 KB Created: 2021-07-22 05:49:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: cf9c95abf0082e928c1e1ce8ebbbb4cd SHA-1: 09cc1fc50aae19dbf37e67311a08ff4a78535e9f SHA-256: b427a8349e7783eb2c2273c2f812b776bb41c3c94df41eb63d7f40adb82eec43
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The ML classifier and ClamAV detection strongly indicate malicious intent. The PDF contains a link farm pointing to numerous compromised CMS upload locations and disposable hosting, suggesting an attempt to distribute malicious content or conduct phishing. The presence of multiple external URIs and a link farm heuristic confirms the document's purpose is to redirect users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9852

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://torbay.ru/images/uploads/file/654819853.pdf In PDF document text
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/9c3b2c544301ad423c9802c61ed5b73b/58172831397.pdfIn PDF document text
    • https://takeorders.online/wp-content/plugins/super-forms/uploads/php/files/vevofkdnmbgeohas0gv32lqr8l/nedafasasadivasosi.pdfIn PDF document text
    • https://www.kadinlarsitesi.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607899429d05f---83216215226.pdfIn PDF document text
    • http://grupophi.es/uploads/files/rugapokari.pdfIn PDF document text
    • https://afd.me.uk/wp-content/plugins/super-forms/uploads/php/files/mgulcamf14o089di7mih52ts6h/80672081666.pdfIn PDF document text
    • https://majorsagilekvaros.hu/uploads/file/54131981972.pdfIn PDF document text
    • https://repare-ton-smartphone.com/userfiles/file/nutobozovo.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/22657780502.pdfIn PDF document text
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/f030b415a4c02db1c9f55db9ab87a72f/15604690919.pdfIn PDF document text
    • https://cakesandcupcakes.net/userfiles/files/nevabusineronuwor.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608106eeee0b2---54605277257.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/dd8efa4b0beaa73eef4ad49c2c9a4cfd/27000054684.pdfIn PDF document text
    • https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/86b57fc55ac7c23c5bf8e3f9279247ae/41415726739.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1606f55804e9eb---nifowivulizog.pdfIn PDF document text
    • https://olympicwroclaw.pl/zdjecia/fck/file/laxasaxerofurirokiz.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a31df0f2985---11208805620.pdfIn PDF document text
    • http://przychodnia-felinskiego.pl/uploads/editor/file/14476520676.pdfIn PDF document text
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/3a871489b9f6dc4ba67ce9ad7ed589f6/vutowitukesujinikadosup.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/73289b20141df81588d03209c244def2/pagevesezaguviruwe.pdfIn PDF document text
    • http://alkanboya.com/files/file///60137978301.pdfIn PDF document text
    • http://mppscstudy.com/admin/usercontent/file/xudilojumudepira.pdfIn PDF document text
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/tqnr9u4b0oup29ddmfbaq36hf7/zejabakikupufa.pdfIn PDF document text
    • http://gursakaryahukuk.com/images/file/mogavinufelowu.pdfIn PDF document text
    • http://trendybiz.in/usersfiles/file/xudox.pdfIn PDF document text
    • https://ferado.vn/userfiles/file/68510440273.pdfIn PDF document text
    • http://prospekt-rostov.ru/ckfinder/userfiles/files/nalununomulobifam.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=repentance+always+comes+at+lastPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001235d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1235D 10588 bytes
SHA-256: 0a3c3c4135b2f2d1d2dd826206262dde7417bcd35056ecd0d01b1b18520adb61
font_01_sfnt_off00013bac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BAC 16588 bytes
SHA-256: 38e360d21b1ca056dfbb6ab4c445dbba48b528cebe4c235bab2644380102024f
font_02_sfnt_off000152e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x152E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off00016af3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16AF3 19436 bytes
SHA-256: 3ed907dd4cd0ed95380618f4e8da991a6f97089669700078f6d3e76a0b12e51d