Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c4c242afd83b860…

MALICIOUS

PDF

75.3 KB Created: 2021-07-31 08:57:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 301885eadefe39459bacdcc6b302209d SHA-1: 736ba4c2142aa0ee5a8e4c98cca7615ce39a1409 SHA-256: 7c4c242afd83b860c7775cc6d16362a6af35e37f81072ea6e8fdfd7908c1cfe9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to disposable hosting or compromised CMS upload directories, suggesting a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of a phishing or malware distribution lure, likely delivered via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • 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 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://syuncyoku.jp/upload/file/sewedowugotute.pdf In PDF document text
    • https://proxus.nl/file/jofepavokalomewotepa.pdfIn PDF document text
    • http://agriturismolataggiasca.eu/userfiles/files/45414751697.pdfIn PDF document text
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/160fe68d9f20b2---80311262414.pdfIn PDF document text
    • http://hopkinshigh1988.com/clients/75739/File/numigosotufimo.pdfIn PDF document text
    • http://digjamaica.com/app/webroot/files/bilebigevo.pdfIn PDF document text
    • https://diaochue.vn/userfiles/file/94263536534.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///72740445705.pdfIn PDF document text
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16098b87ce32cf---taginufenenefep.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c87dc1ff54---tubalojojurekemewamazaba.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/160f66e5e4aa70---60856314591.pdfIn PDF document text
    • http://erpos.sk/data/files/95638248635.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16073d5949712d---95688250600.pdfIn PDF document text
    • https://alamansyria.com/userfiles/file/31958439893.pdfIn PDF document text
    • https://athensviptour.com/wp-content/plugins/super-forms/uploads/php/files/00b10a31308f7c496cd40529fc8bc22d/95250956917.pdfIn PDF document text
    • https://agentcctv.com/userfiles/file/lijugobijilarajapixeda.pdfIn PDF document text
    • http://thelonerangerfanclub.com/ckfinder/userfiles/files/7515958240.pdfIn PDF document text
    • http://dr-onesrl.com/userfiles/files/98078993913.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092caf19d4ab---70409751997.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160e392d6897f8---wirenoleza.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=libro+de+historia+sexto+grado+2016PDF 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_off0000c006.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC006 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d818.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD818 17536 bytes
SHA-256: 2061af3e67a308be5e807793878463b1b6821d1f1f4195a06ec5a8ede86b90d2
font_02_sfnt_off000104a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104A9 11036 bytes
SHA-256: 3dc1607b843323e6221dd46166abc3d9de74c02905cae47fe4c22f457d968ae9