Malicious PDF — malware analysis report

Static analysis result for SHA-256 7eda6d9c49d54e08…

MALICIOUS

PDF

70.2 KB Created: 2021-09-28 01:54:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ffb6d3a816c4eb32884143d28bbee6f5 SHA-1: 5f6ed545055d67054b834aef697731064f8d2f0b SHA-256: 7eda6d9c49d54e0886d6a67b3503021c8026046978839213e077177f094bb9be
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which are part of a link farm hosted on disposable domains, a common tactic for phishing and malware distribution. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://coretry.ru/uplcv?utm_term=ps3+apk+games PDF link annotation
    • https://immo-macedo.lu/userfiles/files/22270308178.pdfIn PDF document text
    • http://yujinpharma.com/upload/files/ropolilovuwibo.pdfIn PDF document text
    • https://loppisidjupdalen.se/images/uploaded/file/niwizedepowadoraxowoj.pdfIn PDF document text
    • http://dekogard.net/deko/veri/_files/lekotebebaxakek.pdfIn PDF document text
    • https://profm.hu/files/file/29363213692.pdfIn PDF document text
    • http://nandishoverseas.com/UserFiles/File/tezepejo.pdfIn PDF document text
    • http://custom-mugs-factory.com/uploadfile/files/jizekirenifuzubanubone.pdfIn PDF document text
    • http://longbeach.ilovepokebar.com/uploads/files/xifedijifuvetefexukos.pdfIn PDF document text
    • http://thechitay.com/uploads/userfiles/file/xosisobubaxovumidejawe.pdfIn PDF document text
    • http://icsbc.ru/fuploader/file/jevaserifobopipiwowimaxas.pdfIn PDF document text
    • http://frchem.cn/upload/files/fifukepavulirorenaxupomab.pdfIn PDF document text
    • https://bozoklar.org/ckfinder/userfiles/files/86175237381.pdfIn PDF document text
    • http://xn--80aafjbaeihgganggf9ajkncugh2a.xn--p1ai/pict/file/27307140613.pdfIn PDF document text
    • https://birutelorasin.com/contents/files/30709870967.pdfIn PDF document text
    • https://santchavarabed.in/ckfinder/userfiles/files/biwoporuxesu.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/ekomsm2d5quq8m63g1rsat6o18/pexiwologedadadub.pdfIn PDF document text
    • https://drhuanghair.com/uploads/files/202109250027037167.pdfIn PDF document text
    • https://cremyco.com/app/webroot/docs/file/87236273071.pdfIn PDF document text
    • https://inprovitperu.com/ckfinder/userfiles/files/9925398817.pdfIn PDF document text
    • https://kentacademymiango.com/userfiles/file/61319452822.pdfIn PDF document text
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614262ed5bd2f---bepumixijumojifi.pdfIn PDF document text
    • http://bkht.vn/userfiles/file/80975776966.pdfIn PDF document text
    • http://fivelscope.net/fckimages/79173056739.pdfIn PDF document text
    • https://0900107678.com/upload/file/mazave.pdfIn PDF document text
    • https://tranhtreo.com/images/ckeditor/files/84110120594.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_off0000b356.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB356 10300 bytes
SHA-256: 6ce9f0c339d55671e6687f7dc816be9fd8713b0d9797c3cbde0800b24a469a70
font_01_sfnt_off0000ca9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA9F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e2b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2B1 15992 bytes
SHA-256: a6967359e80f1f9ccc4610e0dfd77ce71a4283d8c9fc17d7c47a2a54ae693f56