Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb667a50a8a188d7…

MALICIOUS

PDF

78.0 KB Created: 2021-07-25 00:42:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0c298e6dda4ae436a3d8705e862d695d SHA-1: fe4831b3be283a516e93d3dabb9642b834064e84 SHA-256: fb667a50a8a188d766dc00575f75d317ffccec01631c46631c755fa2ca254bf0
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to multiple distinct hosts, many of which are hosted on disposable or compromised domains, suggesting a phishing or malware distribution scheme. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, further obscuring its true purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

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://netinflux.net/userfiles/file/luzutedidug.pdf
    • https://mzr-avocats.com/buddha/ckfinder/userfiles/files/96295872607.pdf
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160974d93c27a9---98471807763.pdf
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086f0aad2d56---wasesupasakozugemoga.pdf
    • https://www.webplease.it/wp-content/plugins/super-forms/uploads/php/files/ulo568s5judol9gajm6dtqis30/fisav.pdf
    • http://magyaringatlanadatbazis.hu/dev/_user/file/diditafatademitilawisedu.pdf
    • http://bbfederico2.net/userfiles/file/rigubidoxo.pdf
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/ef4d4e5e3addc6207e77249ba46c24eb/baninuxaxura.pdf
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6ce3e6694a---fefetifaka.pdf
    • https://scriptdd.com/_file/file/98451574660.pdf
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f3d81b75c5---madokerakamowologaxal.pdf
    • https://genesislighting.net/wp-content/plugins/super-forms/uploads/php/files/cf2ed8fc7c1c561ca9bd733aec607b57/tadutuzimad.pdf
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160875489ab891---tikowipavomajopisut.pdf
    • https://nanyangtextile.com/userfiles/file/ketidaxerosufubazugo.pdf
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/8tbjlsbqdpps9kfdchbjlp6p66/dafop.pdf
    • http://karpatskiles.ru/store/file/lofujifi.pdf
    • https://x-software.cz/data/file/mozupidegak.pdf
    • http://skolicka.eu/foto/images/file/90057652757.pdf
    • https://revapackers.com/wp-content/plugins/super-forms/uploads/php/files/2q7kjh3noi7icot85377o7uafr/63512198654.pdf
    • http://famillespourstarlight.com/clients/a/a9/a9b42c05011d3bb27e7f7ec2ed30324f/File/23903511486.pdf
    • https://bostoncake888.com/UserFiles/files/69565565420.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=integrales+definidas+%C3%A1reas+ejercicios+resueltos+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c95e.bin
1f15389708b50f413a952d498d323f789c39e0df27380b3acf07ade6a00a7d28
pdf-font-stream PDF embedded font (sfnt) at offset 0xC95E 17700 bytes
font_01_sfnt_off0000f65f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF65F 16792 bytes
font_02_sfnt_off00010e76.bin
19ff55c913fc8745b3749b1ca528839537b858d235929049141fd272229d4e43
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E76 11156 bytes