Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e90f77d6e4745f6…

MALICIOUS

PDF

79.5 KB Created: 2021-10-06 06:22:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: b61339fe82aa65f451ec47eb9b253f47 SHA-1: 76d2897558d4d1b86f14660d6d16c96f25bb2e4b SHA-256: 4e90f77d6e4745f6c61d03e48eac0636ab4d952bc86e8140533b807207120c67
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by a machine learning classifier and ClamAV as malicious. It contains numerous embedded URLs, many pointing to potentially malicious domains, and exhibits characteristics of a link farm designed to redirect users. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a high volume of links on disposable hosting, suggesting an attempt to obscure the final malicious destination. While no scripts were explicitly extracted, the nature of the embedded URLs and the link farm heuristic strongly suggest a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://lochoanggia.com/upload/files/pavefiratetefobabiripo.pdf In PDF document text
    • https://gelblighting.com/userfiles/files/mexelemis.pdfIn PDF document text
    • http://antwerp-reefer-tournament.be/argt/files/35180654881.pdfIn PDF document text
    • https://stmpallet.com/ckfinder/userfiles/files/rozapuritetomuboz.pdfIn PDF document text
    • http://tomaszfilipczak.pl/userfiles/file/9969257826.pdfIn PDF document text
    • http://hyunsin.net/userfiles/file/83420202588.pdfIn PDF document text
    • http://ecilingirler.com/resimler/files/gajuzebuzikafagevem.pdfIn PDF document text
    • http://refmexgl.com/web/uploads/assets/userfiles/file/zafafumulonip.pdfIn PDF document text
    • https://haidangpc.com/contents/files/9395208889.pdfIn PDF document text
    • http://businessplan-capalpha.eu/mbp/upload/images/images/upload/ckfinder/ruxosifunebamuv.pdfIn PDF document text
    • http://wedooverseas.com/userfiles/file/88134630593.pdfIn PDF document text
    • http://heatexchangersolution.com/upload_fck/file/2021-9-11/20210911131316740164.pdfIn PDF document text
    • http://amidoux-peintures.com/ckfinder/userfiles/files/kuvive.pdfIn PDF document text
    • http://livestreaming.group/wp-content/plugins/super-forms/uploads/php/files/hd2qtu0249h80hm9riqhri6o9aaaa260/wegex.pdfIn PDF document text
    • http://ciccioinpentola.com/userfiles/files/ronolisisa.pdfIn PDF document text
    • https://arabadvertise.com/userfiles/files/zavipoxifalalixuduwit.pdfIn PDF document text
    • http://gameometria.com/assets/ckfinder/core/connector/php/uploads/files/89995990356.pdfIn PDF document text
    • http://budropol.de/Upload/file/7926163911.pdfIn PDF document text
    • http://elrey-uslugi.ru/media/file/90568580332.pdfIn PDF document text
    • https://agermag.ro/mm/file/81189528525.pdfIn PDF document text
    • http://unitez.net/images/newtech/files/50758096132.pdfIn PDF document text
    • https://web-dev.ethioapp.com/websites/lightyearsahead/code/userfiles/files/61404260204.pdfIn PDF document text
    • http://vitajeans.com/ckfinder/userfiles/files/bitamipi.pdfIn PDF document text
    • http://cokhiminhhien.com/media/ftp/file/wogaxitu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=test+tcp+connection+windows+10PDF 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_off0000cdb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDB8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e5cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5CF 10420 bytes
SHA-256: 2ede8455bd566908b8b070dc22a7e5ec2816fe40f08ca214627db80f0784198e
font_02_sfnt_off0000fda4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDA4 19152 bytes
SHA-256: d8393bccae824477ee79e66287a617506d7b3a5a4548a854cdfd4bec02e00608