Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab95bbb2e3318121…

MALICIOUS

PDF

99.4 KB Created: 2021-09-09 14:33:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: debe5fce9a1b27434bd070eec66f41ef SHA-1: 042809b5a164960db67fdd42fe0d22096f3ff9c3 SHA-256: ab95bbb2e3318121d67d7a959a4bab6792718f3a43d36cc61b698f54efd37b35
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to numerous external URLs, one of which is `https://oniceh.ru/uplcv?utm_term=poetas+malditos+pdf`. The presence of embedded URLs and the link farm nature strongly suggest a phishing or malware distribution attempt, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9865

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://oniceh.ru/uplcv?utm_term=poetas+malditos+pdf PDF link annotation
    • http://www.ctmmaximoravenna.com/ckfinder/userfiles/files/74084107581.pdfIn PDF document text
    • http://ateliergermain.net/sites/default/files/file/48283467327.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613066736ccdd---vitozurasikodibevomabubuz.pdfIn PDF document text
    • https://congthuonghotel.vn/app/webroot/files/images/pages/files/gamobarorulixesuzi.pdfIn PDF document text
    • http://norilskgu.ru/userfiles/file/90454901993.pdfIn PDF document text
    • http://floral-design-lindgens.de/userfiles/file/4170571741.pdfIn PDF document text
    • http://vector-luczak.pl/new/fck_user_files/file/popuzaxozikivopulezebemo.pdfIn PDF document text
    • http://tyextractor.com/d/files/7922592068.pdfIn PDF document text
    • https://stmpallet.com/ckfinder/userfiles/files/51227760674.pdfIn PDF document text
    • https://epiphanych.com/images/file/42709144269.pdfIn PDF document text
    • http://www.yoko-ono.be/images/userfiles/file/murixevizu.pdfIn PDF document text
    • http://willowslakerhea.org/userimages/65324256013.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/rukekelopavosineludo.pdfIn PDF document text
    • http://fpempresa.cen.es/userfiles/files/kupuranewadefejilux.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/16139198727751---15033842701.pdfIn PDF document text
    • http://hindustanadvancedsolution.com/t/tutorfirm/uploads/ck/files/vixajetadedizojelavoxid.pdfIn PDF document text
    • https://eyescare.vn/app/webroot/upload/ckfinder/files/66564053251.pdfIn PDF document text
    • http://podhoru.cz/userfiles/file/duxumavon.pdfIn PDF document text
    • http://techsystem.gr/data/uploads/ckeditor/files/20371633055.pdfIn PDF document text
    • https://carlojans.com/cms/file/68050485640.pdfIn PDF document text
    • http://stringquartet.biz/web/images/fck/file/kolegex.pdfIn PDF document text
    • http://www.agenbenangbandung.net/file/9670650352.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/sobasuzomexotefexifiwamo.pdfIn PDF document text
    • http://abaj.cz/UserFiles/File/94255731963.pdfIn PDF document text
    • http://pietroquatriniarchitetto.eu/userfiles/files/4277741288.pdfIn PDF document text
    • http://bubb.cn/up_file/file/molalawixavimozonogome.pdfIn PDF document text
    • http://rcot.by/pics/files/xuriz.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_off00011d21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D21 20148 bytes
SHA-256: 3b86337019debd2e95686fefb68f757b947779585ec5f6cc69f7a9bcfdc7da67
font_01_sfnt_off00014ff3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14FF3 10456 bytes
SHA-256: 570c07de7faea41c1315d549d193879f2ddb25602ac7102579908770f90948b0
font_02_sfnt_off000167b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x167B3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1