Malicious PDF — malware analysis report

Static analysis result for SHA-256 77707dc149bad8f0…

MALICIOUS

PDF

74.1 KB Created: 2021-06-09 14:07:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: 24249cb097b7b0ee19923a1eef71ab9b SHA-1: 5e4d774cdf2ee853336957828643f182929753b5 SHA-256: 77707dc149bad8f025e060063ae2c6eb09a6773233ec371c06d270987ede5bf0
156 Risk Score

Malware Insights

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

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous embedded URLs, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated and contains no discernible user-facing content, further indicating a malicious intent to obscure its true purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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 https://archism.ru/uplcv?utm_term=formula+of+orthocentre+in+coordinate+geometry PDF link annotation
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160924a5cb0fb9---jenurumefobiwuxiluzodoso.pdfIn PDF document text
    • http://asiavent.com/UserFiles/file/%5C/11074021067.pdfIn PDF document text
    • http://moristas.com/userfiles/files/gunoton.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/cacbda9a2e8b370502fb2e7872c401c8/pukukibikusulumaxoxisifaj.pdfIn PDF document text
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ba76b2d41ce---14648000535.pdfIn PDF document text
    • https://tort-art.ru/userfiles/file/97780464073.pdfIn PDF document text
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/87f744a1db5963e977b6c7b1a112d70c/95321914012.pdfIn PDF document text
    • http://aihyang.com/userfiles/file/25114031199.pdfIn PDF document text
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/cdf80fd447ee8a3fb898e790b0fba6b6/dozizufaweloji.pdfIn PDF document text
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/722c521b0874700b735efe49446af763/luremafozijozoko.pdfIn PDF document text
    • http://scheiden-maassluis.nl/uploads//file/petiwejizujodirigitij.pdfIn PDF document text
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/4e58a33542824f9059c174a49eab9b18/54668078020.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/160722e0c45fcb---38215999072.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0520c9554f---jafegopefop.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c4700354c8---67705710637.pdfIn PDF document text
    • https://askopenko.com/wp-content/plugins/super-forms/uploads/php/files/1dae556c3162dbb3992dba45d15f14c3/37842400578.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099e5317a7a6---55102623447.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e0e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0E1 5316 bytes
SHA-256: 4dd11c81b8eeaf353691087b6dab9d420d94c277da0f5cd7bcef27f419b6cde9
font_01_sfnt_off0000f2d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2D0 11848 bytes
SHA-256: fb1eb39b498e878dc0e71f2b673dd1c4185fd2c1f73cff72be18c711f07a770f