Malicious PDF — malware analysis report

Static analysis result for SHA-256 91cdc4e302e4b693…

MALICIOUS

PDF

80.2 KB Created: 2021-09-19 13:59:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 99204affd64ec29a14532cf93070ccde SHA-1: 14b85ac312f660c5a18270309c84ba1a93b78886 SHA-256: 91cdc4e302e4b693b9fa1bfa228f1a2afe7d6f070ef90d1d723b464028a313cf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous embedded URLs, many of which point to potentially compromised or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URI heuristics and link farm indicators strongly supports a phishing or malware distribution attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://agt.es/files/galeria2/files/34182563699.pdf In PDF document text
    • http://angelascanu.it/uploads/file/vigul.pdfIn PDF document text
    • http://wangguanhardware.com/userfiles/file/baparamelilafitumogagemin.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/hcp5viqg21qvgvgabgdcudkiqu/lemakakovulixodine.pdfIn PDF document text
    • http://ccspatti.org/userfiles/file/16007733236.pdfIn PDF document text
    • https://lokmangal.co.in/wp-content/plugins/super-forms/uploads/php/files/d4c7f8e8a15417241b3d52d973d1b3a5/392216772.pdfIn PDF document text
    • http://hotelclinton.it/userfiles/files/41567025942.pdfIn PDF document text
    • https://ylwlgwadmin.ylwl.cn/upload/files/repepigaronoranebun.pdfIn PDF document text
    • http://f-okinawa.com/img/tmp/files/80366628428.pdfIn PDF document text
    • http://agriturismolescuderie.eu/userfiles/files/4517247110.pdfIn PDF document text
    • http://teresachild.com/upload/files/senejamalo.pdfIn PDF document text
    • http://www.satit.nrru.ac.th/satit/_Adminis/ckfinder/userfiles/files/73334615521.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132b5f330b81---90387793842.pdfIn PDF document text
    • http://meteoratourismactivities.com/files/files/42591818941.pdfIn PDF document text
    • http://shangyi-pump.com/uploads/file/101231222668.pdfIn PDF document text
    • http://weingut-suppan.at/files/zadibinim.pdfIn PDF document text
    • http://synphabase.ch/upload/file/18857326914.pdfIn PDF document text
    • http://sujitonweb.com/userfiles/files/96053615563.pdfIn PDF document text
    • https://ghnservizi.com/file/rutajoza.pdfIn PDF document text
    • https://tutorbolivia.com/userfiles/file/xejude.pdfIn PDF document text
    • http://lexen.ca/userfiles/files/89961124179.pdfIn PDF document text
    • https://52fantasies.com/home/holly/public_html/ckfinder/userfiles/files/26969143104.pdfIn PDF document text
    • https://communeouchamps.fr/userfiles/file/85957998765.pdfIn PDF document text
    • http://bsbcarpet.com/userfiles/file/gopaso.pdfIn PDF document text
    • http://colantuono.it/userfiles/files/93632948032.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=name+five+functions+of+the+skeletonPDF 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_off0000d682.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD682 17128 bytes
SHA-256: 84cbbc29b3e7876463612bee77d67b88e56eb8b1195c5e295c15faa869f6328d
font_01_sfnt_off0001022b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1022B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011a42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A42 10736 bytes
SHA-256: e39ae212f955669a82cf3d3d39d2e6a5ec758c071650ec1c8e9f34cc6260ca83