Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ac2edfa19252ac1…

MALICIOUS

PDF

82.3 KB Created: 2021-09-10 22:44:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 98f761cc4a5d1786cc49f2bc3db324c4 SHA-1: 4d9fc7ba85b3b246d1a7b25d7736b88cccbb4a34 SHA-256: 8ac2edfa19252ac1668c37341d9b699f083cce8f6adfce31eef0b606f073c0e6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics indicate the PDF contains a link farm pointing to compromised WordPress uploads and disposable hosting, suggesting an attempt to distribute malicious content or phish users. The document body is heavily obfuscated and unreadable, providing no further context.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://cructi.ru/uplcv?utm_term=phone+not+updating+apps PDF link annotation
    • http://cokhihoangvinh.com/uploads/userfiles/file/mubogeromovisiremenudewes.pdfIn PDF document text
    • http://indianmailbox.com/assets/images/userfiles/files/27671898153.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138ec213f126---fekazoxarenavoj.pdfIn PDF document text
    • https://guruamardaspublicschool.com/userfiles/files/ravibumapefu.pdfIn PDF document text
    • http://feminella.ro/upload/fck/3339700055.pdfIn PDF document text
    • http://neoneophytou.com/ckfinder/userfiles/files/fibazuzejabokogokuk.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613b7a5817649---12802128595.pdfIn PDF document text
    • https://kingwaterpure.com/ckfinder/userfiles/files/67163249229.pdfIn PDF document text
    • https://charming-dc.com/uploads/files/202109092009135206.pdfIn PDF document text
    • https://sushixusa.com/userfiles/files/81750913414.pdfIn PDF document text
    • https://polnische-zaune.de/userfiles/file/98651368367.pdfIn PDF document text
    • http://virus-safe-zone.com/ckupload/files/rigukovo.pdfIn PDF document text
    • http://miass.realxenon.ru/uploads/files/9761061741.pdfIn PDF document text
    • http://elcwma.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/mugadusosiwabubepuras.pdfIn PDF document text
    • https://jasmijnbloemengroen.nl/userfiles/file/dafunojezizulejiso.pdfIn PDF document text
    • https://dichvuketoansg.com/luutru/files/sivarabigitaxonutilen.pdfIn PDF document text
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/619650b0df797094717e30d4d826530c/25806268024.pdfIn PDF document text
    • https://nicklason.se/ckfinder/userfiles/files/warefi.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/41747812259.pdfIn PDF document text
    • http://nifaelectronics.com/userfiles/file/94245137445.pdfIn PDF document text
    • http://prttour.ca/FileData/ckfinder/files/20210908_E161AA16DA986A09.pdfIn PDF document text
    • http://volareinmongolfiera.it/userfiles/files/rojetug.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_off0000dceb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCEB 18168 bytes
SHA-256: 897250cd9639963cbddf9df7d648ee8f80365b53c2f0dd90efd0ce0044e4a60f
font_01_sfnt_off00010b88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B88 10624 bytes
SHA-256: b04dee27980264c16156f2377ffaa284c48038d2f892edad81b91e4dec472e2d
font_02_sfnt_off00012393.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12393 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1