Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4c1eb211d241c89…

MALICIOUS

PDF

75.4 KB Created: 2021-06-28 02:52:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 8c8b9ef7dbda89654bdab313d76aad0f SHA-1: 681c37afc0c4de5e240be7d184cce57970d0d8b9 SHA-256: e4c1eb211d241c89febd6e2bee970ac498b28093c240d5ad8cb79151a1fb5d1c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links, many of which point to compromised WordPress sites acting as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware distribution sites. The presence of external URIs and link farm heuristics confirms the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606fa803326c8---lozawosusisadiwug.pdf In PDF document text
    • http://fotocaroli.it/userfiles/files/lezurikiwof.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/06ebeecdb582e2c4f50892f2a6cfbe86/87716214910.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/l30cuvcjofo2hkan68vb8ehpk0/nerubuvapufalogizoj.pdfIn PDF document text
    • http://hani-bee.com/userfiles/files/lojiradamizuxepalupurikul.pdfIn PDF document text
    • https://noihoithanhtuan.com/media/ftp/file/dinukevegiruxakad.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c2ba9b3cc7---zesawibefono.pdfIn PDF document text
    • http://amdind.com/userfiles/file/68433313651.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098ae0f85a19---86933767942.pdfIn PDF document text
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/3u2uai4en2kt5bgc719r1uc0g3/33974669425.pdfIn PDF document text
    • http://asea-admin.com/_userfiles/file/20210508163716.pdfIn PDF document text
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/9313f205098d880a1202bf552758485e/xiselakuza.pdfIn PDF document text
    • https://www.hotwaterfactory.com.au/wp-content/plugins/super-forms/uploads/php/files/9c5c6d5b1ab4ee09b7c07cd20118daf5/favapijenupiz.pdfIn PDF document text
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/160803cad80084---dafunadaju.pdfIn PDF document text
    • https://thefertilizerequipment.com/d/files/timudakilevukudi.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/lg36djbafhivrba4e8kh3fjbgh/9468361892.pdfIn PDF document text
    • https://alternativecarrepair.com/userfiles/file/rikonixobumiri.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b784c581e3c---91506560091.pdfIn PDF document text
    • http://isdoor.ru/uploads/files/xefoxofavetikorifopojasa.pdfIn PDF document text
    • http://andlupa.com/userfiles/file/kuzabowutikenedutodabizeb.pdfIn PDF document text
    • http://dlmberatung.ch/userfiles/files/12588341993.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/ivrrnbl534klbg70iuu9rcbc72/19656278772.pdfIn PDF document text
    • https://dungcuruamui.com/wp-content/plugins/super-forms/uploads/php/files/2icpg9277t9r2gsdrc1p9rj6gk/73141923988.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/160d7aa93a656b---vajodukixo.pdfIn PDF document text
    • http://bmcnx.com/userfiles/file/82892319753.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=how+to+find+the+20th+term+of+a+sequencePDF 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_off0000c246.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC246 16676 bytes
SHA-256: 226e6c168acd50211abbdbb0256007d1d27dd6142c1c0acf82edf019e7896879
font_01_sfnt_off0000ede2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDE2 11260 bytes
SHA-256: 6b8da8f167cfc71ab34f15c93f786c230fe5716b56653350348b55f8c4a4ab70
font_02_sfnt_off000107fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107FD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1