Malicious PDF — malware analysis report

Static analysis result for SHA-256 2c873089909dc2c7…

MALICIOUS

PDF

77.3 KB Created: 2021-06-25 19:13:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: d198cb39ba7eafd8f82eda65fb443d5e SHA-1: a4dcb90426ecf0663a744c14e42d3b06c071e3c8 SHA-256: 2c873089909dc2c76f9d796c43067461816097aa73e5c2757792539a65528354
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS upload storage and disposable hosting, suggesting a link farm designed to lead users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL analysis point to a common tactic for initial compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://atut-biuro.com/uploaded/file/58581128871.pdf In PDF document text
    • http://geombiagioschettino.eu/userfiles/files/digakogufonujaxada.pdfIn PDF document text
    • http://bulongvungtau.com/media/ftp/file/wukowapamofovinu.pdfIn PDF document text
    • http://springbook.no/files/52480573761.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c66b7b41548---39014175225.pdfIn PDF document text
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160b467d0eed96---18512935879.pdfIn PDF document text
    • http://cukierniabrzezinski.pl/www/artizam/fck/file/7384154269.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb407c5283---97246128929.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb26e45abf1---xagixuxadomesezudol.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16086c02c92028---wepawozurolak.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aac35941640---dafabanojetafafu.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606d2dc181faa---33554460280.pdfIn PDF document text
    • http://dotacjedlaoze.pl/userfiles/file/40653011265.pdfIn PDF document text
    • http://humanitool.ru/userfiles/file/kusepaketidexikepa.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d00c00bc50---rukavemifeva.pdfIn PDF document text
    • http://turar-mussin.com/userfiles/File/47140690559.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b0f0b29e981---68577733660.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ac791200721---dajokusolirub.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/a62840e577cded38bae541ca3f052ab0/45580214801.pdfIn PDF document text
    • http://dokumsuzgec.com/userfiles/files/gomovokikolokeg.pdfIn PDF document text
    • http://dirabrealtors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607acc5806f28---46171140526.pdfIn PDF document text
    • http://baohanhranghm.com/upload/img/files/tabiderelirurapojanewin.pdfIn PDF document text
    • https://www.kbstephens.com/wp-content/plugins/super-forms/uploads/php/files/1243eeb39cb1323f40fa7f9fbc44fdd8/xirebifaburibafaxetefebim.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=free+online+pdf+converter+to+word+for+editingPDF 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_off0000cc85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC85 10592 bytes
SHA-256: 567dc60e72773a6e2fcefc20dd280068386bd539d2785cc2323c7e2e3573f9ae
font_01_sfnt_off0000e496.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE496 16612 bytes
SHA-256: 1b46f41a4ca507f7d1f3c8c3a65047088abe0cfccc34ae390229eeb504f1469d
font_02_sfnt_off00010fed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1