Malicious PDF — malware analysis report

Static analysis result for SHA-256 921c442aa6f55175…

MALICIOUS

PDF

83.9 KB Created: 2021-09-17 04:45:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 9902cd335c7071a11556eee34ca26940 SHA-1: 6cc5326ddbf9fe1bb7925ec88e7e67c1a38af1ca SHA-256: 921c442aa6f551757d04cd1fa3009bbdf94c0dcd38fd5bfa8106ac0b6871a74a
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. It contains numerous embedded URLs, many of which point to domains that appear to be part of a link farm, suggesting an attempt to redirect users to malicious content. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly indicates this malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://huntic.ru/uplcv?utm_term=android+mobile+hard+reset+software+for+pc PDF link annotation
    • https://optimumquestsolutions.com/ckfinder/userfiles/files/67882950687.pdfIn PDF document text
    • https://www.colline-eternelle.com/ckfinder/userfiles/files/42646417713.pdfIn PDF document text
    • http://donghotam.com/luutru/files/1776406065.pdfIn PDF document text
    • https://prestinireedcorp.com/userfiles/files/23426458189.pdfIn PDF document text
    • https://elsa-daulte.com/ckfinder/userfiles/files/30948935122.pdfIn PDF document text
    • http://metalzilemboeventi.com/userfiles/files/kilatazaxaxigafale.pdfIn PDF document text
    • https://ev-owners.jp/userfiles/files/7122314742.pdfIn PDF document text
    • http://xn--22cjbbm2eyae3ehabdb4kqdtae3dxnnc1fhf.com/user_img/files/darupa.pdfIn PDF document text
    • https://jiu-hang.com/upfiles/editor/files/jasaso.pdfIn PDF document text
    • http://feminella.ro/upload/fck/webipekilin.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/4960d1b81b8136b27fd998af239770cb/70419773163.pdfIn PDF document text
    • http://jodhpurheritagewalk.com/images/file/xobux.pdfIn PDF document text
    • http://mistral-paints.cz/userfiles/files/liworaneduxu.pdfIn PDF document text
    • http://elementsgogreen.com/userfiles/file/musumopigudexexufed.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/d1c62226c6b35051b27d1fd06922f41c/30156426093.pdfIn PDF document text
    • http://phuongdonggolf.vn/app/webroot/uploads/files/fofupididene.pdfIn PDF document text
    • http://kovovyroba-nosniky.cz/UserFiles/File/39963716901.pdfIn PDF document text
    • http://citescolairedeledit.com/include/file/mubijex.pdfIn PDF document text
    • http://creaorganization.com/depo/sayfaresim/file/48492227635.pdfIn PDF document text
    • http://www.radeton-cz.vasestranky.cz/ckfinder/userfiles/files/58255873887.pdfIn PDF document text
    • https://hklh.vip/data/attachment/file/37450781884.pdfIn PDF document text
    • https://nikoljski.com/ckfinder/userfiles/files/xisokokixobedigamamut.pdfIn PDF document text
    • http://geo-equipe.it/userfiles/files/zarolopaloveriwebeli.pdfIn PDF document text
    • http://qlionshousing.ca/userfiles/file/40539117200.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_off0000e03c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE03C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f853.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF853 11092 bytes
SHA-256: da98541d9e1b2eadc7de561b2db05ba6bde3cfc010c0f0fc212b92e0b51c1c35
font_02_sfnt_off000111d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111D3 18372 bytes
SHA-256: dc122d891e77337677be4b11a21f0a83675939d41f622c69a78a2ff561984d49