Malicious PDF — malware analysis report

Static analysis result for SHA-256 f1836732d4d0cf09…

MALICIOUS

PDF

68.9 KB Created: 2021-09-24 19:14:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 368c61642b7ad983eb55a66a94023599 SHA-1: 4241cc333e4bd5b12b1219188f28564bbdc075a6 SHA-256: f1836732d4d0cf0934523f4d9a6f5743eccff986e4ec6eba84ef1bde0bd0e6f4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links, many of which point to disposable hosting or compromised CMS upload storage, suggesting a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of external links and the nature of the hosting used point towards an attempt to redirect users to malicious sites, potentially for downloading unwanted applications or further malware.

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://cistenivytahu.cz/upload/file/lijomuke.pdf In PDF document text
    • https://classoft.ro/userfiles/file/49412256120.pdfIn PDF document text
    • http://93564497.com/userfiles/wudakopopokij.pdfIn PDF document text
    • https://pirkitpadangas.lt/ckfinder/userfiles/files/54678096610.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138b287123f8---84709252586.pdfIn PDF document text
    • http://qwerty.pl/_data/file/77328962454.pdfIn PDF document text
    • http://millecolori.it/images/file/zijejefokufutabifuki.pdfIn PDF document text
    • http://pnc21.com/files/fckeditor/file/1261634469613b2979088a9.pdfIn PDF document text
    • https://cedria.es/DOCUMENTS/FotosFCKEditor/file/zidaditeramopofeka.pdfIn PDF document text
    • https://proetcontra.hu/userfiles/file/25066697057.pdfIn PDF document text
    • https://moma-restaurant.com/wp-content/plugins/formcraft/file-upload/server/content/files/161467d3d7723b---sadizenofivovemigoni.pdfIn PDF document text
    • https://matteagianotti.ch/userfiles/files/82056058041.pdfIn PDF document text
    • http://galeriejacqueselbaz.com/userfiles/file/ralunogu.pdfIn PDF document text
    • https://its-bulgaria.bg/files/file/fajase.pdfIn PDF document text
    • http://vallovin.it/userfiles/files/modigopo.pdfIn PDF document text
    • http://mosvag.ru/img/lib/file/21599396849.pdfIn PDF document text
    • https://propertiproperty.com/Uploads/userfiles/files/xepadejozosonobugosibomij.pdfIn PDF document text
    • http://czpohledavky.cz/userfiles/files/98102537285.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/jukinapexini.pdfIn PDF document text
    • http://leeclinic.kr/userData/board/file/gaxifuwini.pdfIn PDF document text
    • https://smlstripedbass.com/home/rock/public_html/ckfinder/userfiles/files/fumakatevewedowow.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142182ebf772---nusikujij.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=xollu+movie+app+download+for+androidPDF 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_off0000acfe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xACFE 10652 bytes
SHA-256: 69c4cb5d4a4d76c6202c3cbe17dbb0f2fbf62236b1e124839edfca21d41f5cfe
font_01_sfnt_off0000c552.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC552 15240 bytes
SHA-256: daa1ef794aa7521ce64625023c41b149e80ea4f767338f98f5a84a59c1b15610
font_02_sfnt_off0000ec5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC5D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1