Malicious PDF — malware analysis report

Static analysis result for SHA-256 634f99f4c75d92dd…

MALICIOUS

PDF

86.1 KB Created: 2021-06-29 06:41:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 9b0a85c5996c128d35101e83d959a1ea SHA-1: b989e3d3aa4157c5585f3630e07d16c31171d877 SHA-256: 634f99f4c75d92dd4205065c154e671623b2b2d65916bb1be8e9ac4fd432c6e0
196 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and exhibits characteristics of a link farm. It contains numerous URLs pointing to compromised WordPress installations, likely intended to lure users into downloading further malicious content or visiting phishing sites. The ML classifier also flagged this PDF with high confidence.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/7d4ea1f62ef26d8461404a751b5813f1/lekotinened.pdf In PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ab255c8d4e---kuxonibirofirutaviripuk.pdfIn PDF document text
    • http://www.misshandicap.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607522d0d542f---95319399927.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/rj6juddolpfambkc7mjdoqm6b3/15742836679.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/160abc7290c9ca---67874240397.pdfIn PDF document text
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/160982e2b6a9ae---duzojaxepapuvinakobagabi.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076e70e050b4---zubepa.pdfIn PDF document text
    • http://geoodwierty.pl/files/file/bipizubefagili.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7df5ee2e0---30434233211.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0c6659ff84---notafitunawakupat.pdfIn PDF document text
    • https://kaptenhoki.com/contents//files/vofitasevaso.pdfIn PDF document text
    • http://vimbark.sk/editor_uploads/files/jinepevokas.pdfIn PDF document text
    • https://cornwallstaffagency.com/userfiles/file/zimaxalunadukedeka.pdfIn PDF document text
    • https://leganordavigliana.it/uploads/file/19455854805.pdfIn PDF document text
    • http://autoscuolepintozzi.it/userfiles/files/99570533667.pdfIn PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/1b073d3fbcba0882aeca4c3c5f3887a0/lugekebixunevufofu.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b33f6415151---tozidawivapiritisaxerusan.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/678f78d42e4a7cc8522585c16aa899fc/860027184.pdfIn PDF document text
    • https://frontiersneurophotonics.org/wp-content/plugins/formcraft/file-upload/server/content/files/1/160ab215163fff---6110993858.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/mlp24jnnhqkvms1mplvatvr0i7/68210939960.pdfIn PDF document text
    • http://brandiassociati.it/userfiles/file/29687771090.pdfIn PDF document text
    • http://geoplan.su/userfiles/file/47337412011.pdfIn PDF document text
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/0624617c4cdeb6556c1dd9adfd7b3ec1/71597373516.pdfIn PDF document text
    • http://dirabrealtors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d210309735d---39536466778.pdfIn PDF document text
    • http://urbancollab.com/userfiles/Proj_Name//files/79155349413.pdfIn PDF document text
    • https://www.lightingdynamics.com/wp-content/plugins/super-forms/uploads/php/files/f454471bfd4b215c737e081d06cbe50c/duwepuwagitagew.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=ice+breaker+question+and+answerPDF 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_off0000ece1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECE1 17240 bytes
SHA-256: 154d6b4c42ca5fdc664d1cc023adb72a9bbf08ad07f30fd9503c4c3cae7c9913
font_01_sfnt_off000119ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119EC 10832 bytes
SHA-256: 785acb990d136be394481173b70ad4e94e9be5baee5f8c90f6014fd89fbfacf8
font_02_sfnt_off000132ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132EC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1