Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4b346ff704f0bd9…

MALICIOUS

PDF

83.8 KB Created: 2021-09-14 03:51:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: dd7d1eb5fdf62261f71919c57587a551 SHA-1: 488fe93d82230b621f1f99eb73c70c4b05c0981e SHA-256: a4b346ff704f0bd9e0e5f7adf212946e0574731dd252fa706a549891a307effe
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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://pixomot.ru/uplcv?utm_term=re4+mobile+edition+apk PDF link annotation
    • https://papiratisk.cz/soubory/36805092347.pdfIn PDF document text
    • http://flirdining.com/uploads/files/makivelagoporabex.pdfIn PDF document text
    • https://angkorphotographyguide.com/userfiles/file/41847997758.pdfIn PDF document text
    • http://merydian.pl/nowymerydian/userfiles/file/2238038962.pdfIn PDF document text
    • http://janaturismointegrato.com/uploads/file/29892342145.pdfIn PDF document text
    • https://onlinendttraining.com/files/mexejezinisuro.pdfIn PDF document text
    • https://mimpiindahsatu.com/contents/files/fuvemexosawamip.pdfIn PDF document text
    • http://bjaimama.com/data/upload/2021/09/file/202109050524039933.pdfIn PDF document text
    • http://dgelc.com/userfiles/file/20210904231142.pdfIn PDF document text
    • http://hide-bo.com/img/tmp/file/53616399503.pdfIn PDF document text
    • http://tvcsoltau.de/userfiles/file/molikuwifoxon.pdfIn PDF document text
    • http://webinaris.blog/ckfinder/userfiles/publics/files/30652424172.pdfIn PDF document text
    • http://toroisg.com/public/images/files/gidotupanufat.pdfIn PDF document text
    • http://firewheels.pe/userfiles/file/4184021837.pdfIn PDF document text
    • http://anhuizhkj.com/upload_fck/file/2021-9-1/20210901062149930886.pdfIn PDF document text
    • http://ressourcengarten.de/azubi/userfiles/files/50863269580.pdfIn PDF document text
    • http://cariboohose.com/userfiles/file/wefigut.pdfIn PDF document text
    • http://huucodatlanh.com/userfiles/file/15143743656.pdfIn PDF document text
    • https://e-casainteligenta.ro/userfiles/file/gudexupawofotilivaruriwuw.pdfIn PDF document text
    • http://hoanhaochemical.com/uploads/files/50253914235.pdfIn PDF document text
    • https://littleedupark.com/ckfinder/userfiles/files/vovezuneledafajigegibal.pdfIn PDF document text
    • http://dakdekkersindex.nl/images/uploads/54998910285.pdfIn PDF document text
    • https://coimbatorepressclub.com/FCKeditor/userfiles/file/wituwazigunusifaz.pdfIn PDF document text
    • http://t-eamplus.de/web/editor/files/lazodad.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/lokojifesuzexuvesas.pdfIn PDF document text
    • https://rosenstein.lu/userfiles/files/13957237109.pdfIn PDF document text
    • https://lean-ds.com/upload/editor/file/20703741345.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_off0000d773.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD773 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF8A 10640 bytes
SHA-256: 81754d3d3ebac3baa0e91f0ec53b4efede7e1cce80fe8de712f2c32f4ea97904
font_02_sfnt_off000107a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107A5 22200 bytes
SHA-256: f70f4e5de8288a3b91e75db4d0eff10478acd6e638095d976962193adeeb3e67