Malicious PDF — malware analysis report

Static analysis result for SHA-256 c94c1d0d30b7315c…

MALICIOUS

PDF

83.0 KB Created: 2021-03-18 23:58:17 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-16
MD5: 6b77d8a474303b14c379c564ef29c1fa SHA-1: b877fcee374e1c7cf25ead5302a083323101a51d SHA-256: c94c1d0d30b7315c1ded18fc1f6fb529f852168b73b47e6877aa1ca1767cd1b8
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, hosting numerous external URIs on disposable domains, such as http://pisibebix.22web.org/girl_in_room_105_online_free_download.pdf. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, a tool often used to create PDF documents from web content, further supporting the link farm hypothesis.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://golowaki.ru/123?utm_term=antigona+furiosa+gambaro+pdf PDF link annotation
    • http://pisibebix.22web.org/girl_in_room_105_online_free_download.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4481156/normal_5ffde71c6cda6.pdfIn PDF document text
    • http://pararapameso.getenjoyment.net/36513523367.pdfIn PDF document text
    • http://kyhni.site/nakajifaneramokefifaz04wg.pdfIn PDF document text
    • http://plsale.pro/royal_caribbean_cruise_stock_price_todaydv6h3.pdfIn PDF document text
    • http://lozomaneje.getenjoyment.net/vanupatimab.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368467/normal_5fd7ba3d1ee02.pdfIn PDF document text
    • http://atomyimperial.ru/parent_partners_pluslnfey.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374189/normal_6011977b17efe.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4392452/normal_6005d47c586ae.pdfIn PDF document text
    • http://betijeduw.getenjoyment.net/diragotasunononanenuk.pdfIn PDF document text
    • http://goladelexugezi.sportsontheweb.net/6559365015.pdfIn PDF document text
    • http://gapofar.22web.org/51946223794.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4372355/normal_600f2c8e5ef78.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/8494b703-770d-4885-bb10-fccbd7887520/vovoradoge.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ea4da5ec-c7d9-4ccf-9c21-11854a454216/50490208469.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/676bac43-88c4-4d71-88fa-9ba586b13bd0/how_to_clean_smelly_dyson_v6.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e4628f02-ec4e-4c18-aeef-e5d8cb7b0c5f/discovering_physical_geography_2nd_edition.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f0bd88a8-0aab-43e0-b7a6-1e6bba1bdc9a/wopakuzanewim.pdfIn PDF document text
    • http://jugorufu.epizy.com/13471352825.pdfIn PDF document text
    • http://vafikozokus.rf.gd/difevifijode.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b013b896-29b9-46bf-aece-7142f9cb07fa/zejetefonubatidip.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a452e11f-575f-4a05-9f70-7ed66ab099d1/what_are_the_four_types_of_categorical_claims.pdfIn PDF document text
    • http://bopenakonaj.rf.gd/92940429301.pdfIn 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
    • 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_off0000efdb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFDB 5456 bytes
SHA-256: 11465ccf76e5aea3e51d1e8ee77314f09ef7d444cd9efa766d75c8b1cec488aa
font_01_sfnt_off00010256.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10256 11324 bytes
SHA-256: 3d7eecb138d4aff02d3061df09c0b61b5673cffd7a75b4fde79f0dad1f6f8457
font_02_sfnt_off00012825.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12825 16060 bytes
SHA-256: 5b0d2701ab39d2f69c66d7d16c60d8db0b323aa0832947137e757b5401d27330