Malicious PDF — malware analysis report

Static analysis result for SHA-256 5adb4a4e686ff3b4…

MALICIOUS

PDF

84.9 KB Created: 2021-07-03 23:03:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 633ee80bbb068fecf2693e81b654236c SHA-1: c7b4e44a5f555b30e5ddb32fcb86702f7454e6b5 SHA-256: 5adb4a4e686ff3b477fecc9599329e91b2fc980901588f23b3b6202c346c8571
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised WordPress sites and other potentially disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or directing users to malicious content. The document body is unreadable binary data, suggesting it's not intended for direct user consumption but rather as a vehicle for the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://pdww.ru/ckfinder/userfiles/files/51052631007.pdf In PDF document text
    • http://szymonadamczyk.pl/uploads/fck/file/sifuzovogawimumij.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160cb613c5d101---muwugimobesin.pdfIn PDF document text
    • http://articolo17.it/siti//usr/foto/files/39283934729.pdfIn PDF document text
    • https://jnvhardoi.org/ckfinder/userfiles/files/lesumevarukobajere.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b26f0dc26f---kutizanul.pdfIn PDF document text
    • https://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/d62be105e02fabf11dfeb5a7c10522b9/13261418248.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607f61bf19a83---71079344587.pdfIn PDF document text
    • https://samngaimarble.com/html_upload/file/35620716826.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/71444fc3586d3478699fb1e6563c12e5/30825117229.pdfIn PDF document text
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/dc1smfae835pq10vfgfcfjj1qt/87672115903.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160acb2ad3564f---73014037879.pdfIn PDF document text
    • https://xn--nmqu14inmf.com/upload/files/wuvobuvikijefi.pdfIn PDF document text
    • http://dok-vo.ru/userfiles/file/48175455260.pdfIn PDF document text
    • https://0286869143.com/editor_images/files/3129223592.pdfIn PDF document text
    • https://baohohoanglong.com/userfiles/file/39559924664.pdfIn PDF document text
    • http://dxqzx.com/ckfinder/userfiles/files/20210630_142511.pdfIn PDF document text
    • https://foundryindia.org/userfiles/file/fafasuxejeneveb.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/16077965e896b6---2113790093.pdfIn PDF document text
    • http://triatlonbizuterie.cz/sites/default/files/file/49840869716.pdfIn PDF document text
    • http://builderall.info/userfiles/file/jerafowoz.pdfIn PDF document text
    • http://monkey-do.net/userfiles/file/rizar.pdfIn PDF document text
    • https://birudongker.com/contents//files/manike.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=gallstone+removal+without+removing+gallbladderPDF 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_off0000e8a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8A9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000100bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100BB 16940 bytes
SHA-256: 5e38d0a134e2dc6fd0c01516ff7b9bc40ffb11a33b97dcbe01c174f4dc5101cd
font_02_sfnt_off00012c72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C72 11128 bytes
SHA-256: 3a672cbcd692227cbcadbe3d571eda34b026e09bd8a377de1eafee7b0743b43b