Malicious PDF — malware analysis report

Static analysis result for SHA-256 85c145e1ad0a3b5d…

MALICIOUS

PDF

79.8 KB Created: 2021-09-16 06:46:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f30d028b0465ddd9ba16af91b89c47b0 SHA-1: 84ac16a1c87ca87fe7a7216d7ce4d24dbcf3e5e5 SHA-256: 85c145e1ad0a3b5de78e39dc1a2d49e6408b074b9c53775ac190e142dfebe621
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous unknown URLs, a common tactic for phishing or distributing further malware. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of multiple PDF-specific heuristics related to URI and link farms further supports this assessment.

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 https://thegmsbihta.in/userfiles/file/46315068354.pdf In PDF document text
    • https://vayamcs.com/content_files/files/36533972107.pdfIn PDF document text
    • http://eko-baby.ru/userfiles/file/78996482404.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/ec8796d4b98c1cb266c33491406de05a/93040264657.pdfIn PDF document text
    • http://leguido.net/files/sedezedemofoxivuger.pdfIn PDF document text
    • http://kirsanov-maslo.ru/uploads/rixoxul.pdfIn PDF document text
    • http://rrarental.org/upload/file/83681537037.pdfIn PDF document text
    • https://businesslife.com/content/file/9573136084.pdfIn PDF document text
    • http://sanruou.com/app/webroot/uploads/files/fawefinulumalubedoxukal.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/161413d72b264d---wikakokoxuw.pdfIn PDF document text
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/1fa9b904c50456131eb9345026278925/56676046914.pdfIn PDF document text
    • http://igigeothermal.jp/userfiles/file/9564916809.pdfIn PDF document text
    • http://coimbra.hu/uploads/ckfinder/userfiles/files/putuwawi.pdfIn PDF document text
    • http://mariekevanvlierden.nl/survey/userfiles/files/bunawutifaga.pdfIn PDF document text
    • http://teewer.mn/ckfinder/userfiles/files/53330500974.pdfIn PDF document text
    • https://transport-vehicules.fr/userfiles/file/mugudibodigotexiziwisosi.pdfIn PDF document text
    • https://appchecar.com/ckfinder/userfiles/files/fidudanoserigiletoxebuxef.pdfIn PDF document text
    • https://csp-pub.com/stockages/files/95504418453.pdfIn PDF document text
    • http://sydjpg.com/images/upload/file/20210912_095221_160.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1613a176f4c5d9---78030264575.pdfIn PDF document text
    • http://tdsns.ru/userfiles/file/wajoxuze.pdfIn PDF document text
    • http://symbolfoods.com/files/file///2163450549.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161391ce255ac1---lejefonobawakupivimagu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=convert+document+to+audioPDF 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_off0000d46a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD46A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC7C 17280 bytes
SHA-256: 5258837a25a3ff739e8c563693b1d2ecfbc4fe3e5a3498e26499f6462f4162ff
font_02_sfnt_off00011979.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11979 10512 bytes
SHA-256: f186057115360c2015d41be8db21b0520b6e7bbd21c8e8939002a89a204cb00f