Malicious PDF — malware analysis report

Static analysis result for SHA-256 493d05d79ee46aaf…

MALICIOUS

PDF

68.4 KB Created: 2021-06-18 18:54:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: f91ea6c26385100814b85ec32bd328f9 SHA-1: a83a95d5b3dc1c626d4e6d705467eb5042370040 SHA-256: 493d05d79ee46aaf677e4c51b30cb3c020d615607f088f2661fef73d24602cc9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was flagged as malicious by ML classifiers and ClamAV. It contains numerous links pointing to compromised websites and disposable hosting, suggesting a link farm or phishing lure. The document body, though heavily obfuscated, contains metadata indicating it was generated by wkhtmltopdf, a tool often used to create malicious PDFs. The presence of embedded URLs and the nature of the heuristics strongly indicate an attempt to redirect users to malicious sites, likely for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/160c8b2de80166---gofitalisewajid.pdf In PDF document text
    • http://bjaimama.com/data/upload/2021/05/file/202105231624055291.pdfIn PDF document text
    • https://gfow.om/wp-content/plugins/super-forms/uploads/php/files/7fvcugj1vu32ufi7q6acueqgb7/dunowupakupuk.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/160ac3f269a703---25736701559.pdfIn PDF document text
    • https://roweryelectra.eu/app/webroot/uploads/file/16206488510493.pdfIn PDF document text
    • https://ikima.fr/uploads/file/89715191245.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b3464a727cf---bugeruju.pdfIn PDF document text
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9f82eee9a---fasunupik.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/9bc69e2716d86ae714a7a6743496a79a/97495123362.pdfIn PDF document text
    • http://emannsltd.com/userfiles/78111611437.pdfIn PDF document text
    • http://interwork.sk/userfiles/file/fapis.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607c759cd3fb2---degamoguwebugaxofedesatup.pdfIn PDF document text
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/d6d7613c58bf526db9bb96063ade5620/fedagewajuxinafivab.pdfIn PDF document text
    • https://www.ideaklinikankara.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bd7582926b---79703918604.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a19d47a2181---82356959067.pdfIn PDF document text
    • https://www.eziblank.com/wp-content/plugins/super-forms/uploads/php/files/b425700e5297c8b19d6e47eead29e7fb/vetomituxipelaguzeve.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/7786725764.pdfIn PDF document text
    • http://shs1977reunion.com/clients/41590/File/54300378733.pdfIn PDF document text
    • https://ahreco.com/uploads/news_file/gibemu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=introduction+to+chemical+engineering+thermodynamics+pdfPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000caee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAEE 5608 bytes
SHA-256: 89b821304e5cb8916df34e01a71eb77f6649036179c05b708c202aed4d6334f0
font_01_sfnt_off0000ddd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDD8 11116 bytes
SHA-256: 72393a00efeb139309e1575b9ae028fd8101a5cece81ee1754a0c34cfd428843