Malicious PDF — malware analysis report

Static analysis result for SHA-256 954a40dbbd23d8a5…

MALICIOUS

PDF

74.3 KB Created: 2021-10-18 03:36:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 7d38630eda4493539f5d80eb3b4ebe9f SHA-1: dc8a4aad08e0287c46a928f844c88a68a35716ec SHA-256: 954a40dbbd23d8a51f642ce1e9623ca8b0803edbd2d4e66932cdd8f1d206b463
126 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, with multiple heuristics indicating it's a link farm on disposable hosting. The PDF contains numerous embedded URLs, many of which are likely part of a phishing or malware distribution scheme. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest it's designed to redirect users to malicious sites, likely as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

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://queure.ru/uplcv?utm_term=introduction+to+word+problems PDF link annotation
    • http://theclelandgroup.com/img/upload/file/vewutigeminupex.pdfIn PDF document text
    • https://webmanagement.jbclub.ro/images/file/52078225319.pdfIn PDF document text
    • http://yas-center.ru/userfiles/file/kamenolutimilanufofede.pdfIn PDF document text
    • https://floraplant.gr/FCKeditor/userimages/file/ginanetodijizukatafivur.pdfIn PDF document text
    • https://melnikhouse.com/userfiles/file/86849267710.pdfIn PDF document text
    • http://lica-mpt.it/userfiles/files/86841790869.pdfIn PDF document text
    • http://www.cavice.fi/tiedostot/files/ziralusakofewolujom.pdfIn PDF document text
    • http://haraj-alqunfudhah.com/userfiles/file/5990481141.pdfIn PDF document text
    • http://printific.com/images/contentimages/files/80011847273.pdfIn PDF document text
    • http://damvua.com/damvua/public/images/files/gomexipinekutesusujumupu.pdfIn PDF document text
    • http://boki.hu/editor_up/mixazederapaburo.pdfIn PDF document text
    • https://isigakizima.net/img/tmp/file/nonavelusimokitegegome.pdfIn PDF document text
    • http://maytinhtuyenquang.com/home/maytinhtuy/domains/maytinhtuyenquang.com/public_html/images/file/milodokorexiduf.pdfIn PDF document text
    • https://maintogelonline2.org/contents/files/bijaburetonifigobamej.pdfIn PDF document text
    • https://organicfertilizerproduction.com/d/files/69417267271.pdfIn PDF document text
    • http://sksound.com/userfiles/file/dejeselopamadonokuremalaz.pdfIn PDF document text
    • http://ilkemymm.com/image/files/35301205396.pdfIn PDF document text
    • http://shrlie.com/upload_fck/file/2021-10-12/20211012192106253308.pdfIn PDF document text
    • https://yucekalipmakina.com/tsrm1/img/userfiles/file/42474620405.pdfIn PDF document text
    • http://e3edu.vn/public/ckfinder/core/connector/php/connector.phppublic/uploadsfiles/temifitesipozalegapolate.pdfIn PDF document text
    • https://icon-studios.com/userfiles/file/fuguresekajum.pdfIn PDF document text
    • http://ud2-140.com/files/97162096569.pdfIn PDF document text
    • http://dvif.fr/userfiles/file/86530781385.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f39b58e3e8---bojokamejurujukusisanup.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/1km3dlvbqn74iic2og9afj7ajs/lebodenuvesixugiwub.pdfIn PDF document text
    • http://symbioticlifetech.org/attfile/fckimg/file///2021091523714_259125770.pdfIn PDF document text
    • http://integrotech.pl/zdjecia/file/93266273547.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://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_off0000c184.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC184 10792 bytes
SHA-256: 92313c75774e057b946d7f53b8f7c7c664606806c0646a47758d52a196e14d69
font_01_sfnt_off0000da31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA31 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f243.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF243 16124 bytes
SHA-256: 2f9292e736773f0d7673dfd18acc7fa06c16038c79e4779a87915f1b7d9da17e