Malicious PDF — malware analysis report

Static analysis result for SHA-256 178043b177a9839c…

MALICIOUS

PDF

73.1 KB Created: 2021-09-19 23:03:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 6dc2049c670d40f0d2ed2274df1cb536 SHA-1: 482d204069e343be255197589a6bf3559d2d1970 SHA-256: 178043b177a9839cd5f224d75deef55c76454981703510dc49c546526db8887e
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 pointing to various domains, many of which are likely part of a link farm designed to obscure the ultimate destination. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using disposable hosting for these links, further suggesting malicious intent. While no scripts were directly extracted, the structure and heuristics point towards a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://ymvii.com/admin/upload/files/rironifaxibaruvumifowe.pdf In PDF document text
    • http://hidramaco.com/files/files/99112874221.pdfIn PDF document text
    • http://sensi-leszno.pl/userfiles/file/74040334937.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/161444bfba93c3---12694130944.pdfIn PDF document text
    • https://inijariku.com/ckfinder/userfiles/files/gabulezozokipebiper.pdfIn PDF document text
    • http://hieuchuan.com/upload/files/gisorusugomusumek.pdfIn PDF document text
    • http://maketmaster.ru/admin/ckfinder/userfiles/files/15760730393.pdfIn PDF document text
    • http://55pluscommunityspecialist.com/userfiles/files/zemewosopenuw.pdfIn PDF document text
    • https://nstoplana.rs/ckfinder/userfiles/files/vozudebamigowog.pdfIn PDF document text
    • http://hasyo.net/files/file/21117288292.pdfIn PDF document text
    • http://chinahongji.com/d/files/48120364160.pdfIn PDF document text
    • http://degeninhotel.ru/admin/ckfinder/userfiles/files/57970379098.pdfIn PDF document text
    • https://g4m3s-4p1-12s1.com/contents/files/73514329040.pdfIn PDF document text
    • https://mollis.rs/files/18169256537.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b6cebebf69---dadidisalupur.pdfIn PDF document text
    • http://tsmsaldature.it/userfiles/files/13093560325.pdfIn PDF document text
    • https://ceiling.holcom.vn/webroot/img/files/85748298029.pdfIn PDF document text
    • http://mediaworld.pro/ckfinder/userfiles/files/71576727704.pdfIn PDF document text
    • https://lawyerupsmart.com/tempimg/file/84871692723.pdfIn PDF document text
    • http://praconsulgroup.ru/pict/file/95481920240.pdfIn PDF document text
    • http://aias.pnu.ac.th/ckfinder/userfiles/files/rafazowetiremexoler.pdfIn PDF document text
    • http://amoy-art.com/Upload/file/puzugu.pdfIn PDF document text
    • https://4wheelchile.cl/admin/uploads/file/90130020167.pdfIn PDF document text
    • http://eco-building.cz/UserFiles/File/18461674891.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=xhamstervideodownloader+apk+for+chromebook+os+rPDF 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://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_off0000bc32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC32 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d444.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD444 15924 bytes
SHA-256: 14b0b9d414e25518c63e32101d550d8abd1dd56e6818c43f72b4b6aa9deb83f9
font_02_sfnt_off0000fcd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCD0 11276 bytes
SHA-256: ed2f965dd7160b4be5f1a7d7926fdc7d58a16e7deff7bbac29ac64da9ef5bbd0