Malicious PDF — malware analysis report

Static analysis result for SHA-256 fff03ea6a042a649…

MALICIOUS

PDF

81.8 KB Created: 2021-09-01 11:10:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 76a05486a92aad3aa9b005f993ad5da7 SHA-1: 7a3c2cec39f3bdf34ab29044c236d5e05e0f35d5 SHA-256: fff03ea6a042a649bb06d6cd9134adc4b663daca141ff4b53ecc81e59663d98f
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as a link farm, with several URLs pointing to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The document body is heavily obfuscated and unreadable, suggesting it's designed to hide its true purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

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://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/1609552986e02b---447517760.pdf In PDF document text
    • https://nothingbutsafetyglasses.com/userfiles/file/vebimuje.pdfIn PDF document text
    • http://www.theflightfest.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8728fbdbb6---sogijowenogewa.pdfIn PDF document text
    • https://anakmeong.com/contents/files/71135281434.pdfIn PDF document text
    • https://toliveinchristjesus.ceosale.catholic.edu.au/application/third_party/ckfinder/userfiles/files/pifox.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c686e13ef4f---tobilaxude.pdfIn PDF document text
    • https://wulf-sanitaer.de/wp-content/plugins/super-forms/uploads/php/files/mqdlp76unq1qjrn4ti7j61tq3h/kebivaxusufigawalakisax.pdfIn PDF document text
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/f28ed64fe1f762cad8f2dad8084e9dce/11428659025.pdfIn PDF document text
    • http://midiabyz.com/wp-content/plugins/super-forms/uploads/php/files/3077f1267dc0658e9c696812df04fa36/jivijipuna.pdfIn PDF document text
    • http://computergramm.com/userfiles/file/rabuvojutojinudas.pdfIn PDF document text
    • https://maviet.vn/upload/files/jekapunonutikilat.pdfIn PDF document text
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160f7beed95cb6---bazorunutadodalij.pdfIn PDF document text
    • http://ampletrekking.com/userfiles/file/paxewa.pdfIn PDF document text
    • https://blueparadise.pl/userfiles/file/11525696835.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc1d730a9e2---73236477373.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/ivh5mocosdfhbv2k0afln4p974/13127188185.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/34285877103.pdfIn PDF document text
    • http://dkkarsin.pl/img/upload/files/zoditijis.pdfIn PDF document text
    • http://ackerviewguesthouse.com/userfiles/file/jedulujogalezet.pdfIn PDF document text
    • http://aozbt.com/clients/3/33/335f642cf73e2ad82edc7dd4a76dad4e/File/15294334733.pdfIn PDF document text
    • https://flvirginia.com/wp-content/plugins/super-forms/uploads/php/files/2cc548f6392197c140ff590a7c198f38/42627904042.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/d8216c48b1252e0b1849eb4b90e3d1b8/16412794455.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/c5jma0hvt9hneh4oj0ku2th932/95933160793.pdfIn PDF document text
    • https://forex-robo.org/wp-content/plugins/super-forms/uploads/php/files/4cedc019e5d506e01cbc101b74485ec1/68375900517.pdfIn PDF document text
    • http://mountcalvary76.com/clients/9/90/9062e1c9f2360b2cedac6e2854879500/File/15576030959.pdfIn PDF document text
    • http://alompar.hu/uploads/content_files/files/bodotaliwewokalepal.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=application+of+calculus+in+commerce+and+economicsPDF 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_off0000da18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA18 17308 bytes
SHA-256: 28a25b11b44d8bc6ef90a6d652031ed6eb2f9bebaed46040d8544ddbc51b64c1
font_01_sfnt_off00010718.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10718 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011f2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F2F 10864 bytes
SHA-256: b61492f91fccd29cde4181bd57e4469d0d3f36d3e6be13806e5609efed9510a5