Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d4bf062dcc06098…

MALICIOUS

PDF

83.9 KB Created: 2021-09-17 10:45:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 5c0cc9dd7ebf9e7853a61b2e728381f3 SHA-1: fd53eb7fcdfd1127520935047f414d31d9743cfb SHA-256: 8d4bf062dcc06098d598b1916877cbb9c43bceac52f23db4ae75c53b5f61de26
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised WordPress sites and disposable hosting domains. These links likely serve to distribute further malware or facilitate phishing attacks.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://catamma.ru/uplcv?utm_term=formula+of+angle+of+sector PDF link annotation
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/r978p7h69vkkovpcl0k2q7bo7r/97351293854.pdfIn PDF document text
    • http://langyupharm.com/upload/files/22123065503.pdfIn PDF document text
    • https://keluargamimpi2.com/contents/files/84463393974.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142befdcc9e7---25939674865.pdfIn PDF document text
    • http://primaneighbors.com/userimages/tufenufolewogoduwalu.pdfIn PDF document text
    • http://gildiamasterov.ru/userfiles/file/mimobisezizevofosulibesip.pdfIn PDF document text
    • http://zlhk.ru/upload_picture/file/bonijuzumotodibenanibovan.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/1612f19c86df7f---65827950760.pdfIn PDF document text
    • http://legalinet.eu/userfiles/files/nopozapubuzovuv.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cd9152ab76---pipuso.pdfIn PDF document text
    • http://villa-margherita.biz/userfiles/files/44855774379.pdfIn PDF document text
    • https://kenkochaya.com/user_data/ckfinder/files/1196961287.pdfIn PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/sld6s69tt3tbb0l16bfqg0lurd/68402083845.pdfIn PDF document text
    • https://esofagopisa.it/userfiles/file/80307766482.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140e48adb0ea---libifolezekopedifubovata.pdfIn PDF document text
    • http://studiochiodo.eu/userfiles/files/603571886.pdfIn PDF document text
    • http://kmbb.at/userfiles/file/1298011664.pdfIn PDF document text
    • https://jin-ji.com/upload/files/miviledapubo.pdfIn PDF document text
    • http://ingegnasrl.com/userfiles/files/fuzivukeligalip.pdfIn PDF document text
    • http://unityproductions.com/upload/files/41632615861.pdfIn PDF document text
    • https://coimbatorepressclub.com/FCKeditor/userfiles/file/85082914094.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131d5d213519---57980317179.pdfIn PDF document text
    • http://srtcivilnorth.com/ckeditor_file/files/2547864854.pdfIn PDF document text
    • http://studioindelicato.com/userfiles/files/pobuwedusivubopiwazubok.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_off0000de74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE74 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f686.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF686 19100 bytes
SHA-256: 9ec5a9e539bc870d835a459bf25851d5941021a07e7975ce120286c8004044ae
font_02_sfnt_off00012962.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12962 10664 bytes
SHA-256: 2916c1be6769fd0b6a91e53fdf31b2ba113e9af31828eb68b9608485d8958164