Malicious PDF — malware analysis report

Static analysis result for SHA-256 105bac6fe654e614…

MALICIOUS

PDF

76.5 KB Created: 2021-09-08 16:03:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 89bb407ea1970f63897c479c32525e3d SHA-1: 6acc6af066f6caf415c2f537202474ba0db5335e SHA-256: 105bac6fe654e614667d45d34452c5404373d31e538e23f251cb9258deae1375
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, with many pointing to domains that appear to be part of a link farm, suggesting a phishing or malware distribution scheme. The presence of external URI heuristics and the 'PDF_SEO_DISPOSABLE_LINK_FARM' firing further support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://aznamaste.com/ckfinder/userfiles/files/dudulazituzanidalugazu.pdf In PDF document text
    • http://dfanchem.com/upload/files/kowedomapafiwowox.pdfIn PDF document text
    • https://srmhomes.com/images/bulk_images/files/kefudogigexopepijoxomanut.pdfIn PDF document text
    • http://facilitymanagementassociates.com/survey/userfiles/files/tuvitunus.pdfIn PDF document text
    • https://jerseyshorepirates.com/userfiles/files/sokitigolalodedonuf.pdfIn PDF document text
    • http://veszpremkosar.hu/_user/file/80196131651.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/33939503411.pdfIn PDF document text
    • https://amzentransportationindustries.com/admin/imagetemp1/file/2431623585.pdfIn PDF document text
    • https://rafautama.com/uploads/file/65911171124.pdfIn PDF document text
    • http://badaranquehablar.com/userfiles/files/7944442986.pdfIn PDF document text
    • http://shengyaweb.com/uploadfile/file/2021090700095460.pdfIn PDF document text
    • http://csim.jp/ckeditor/uploads/files/21939312329.pdfIn PDF document text
    • https://hongdung.vn/ckeditor/images/files/bemoxoxodesajulexevo.pdfIn PDF document text
    • https://dutchfansitenetwork.nl/ckfinder/userfiles/files/sifurodiworipej.pdfIn PDF document text
    • https://xn--23-6kci4asohe8k.xn--p1ai/userfiles/file/82342450503.pdfIn PDF document text
    • http://i-akparat.kz/ckfinder/userfiles/files/tojibukumixasudoratide.pdfIn PDF document text
    • http://dobryremont.pl/ebobas/portal/app/webroot/img/tmp/file/16308983054775.pdfIn PDF document text
    • http://pescepiana.eu/userfiles/files/tagemopibabolabokilepivu.pdfIn PDF document text
    • http://teplolux72.ru/upload/file/varopi.pdfIn PDF document text
    • http://muzycznescyzoryki.pl/userfiles/file/dunegozoke.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613536aa56767---tikazovigokoro.pdfIn PDF document text
    • http://maxbrio.kr/files/files/8601132141.pdfIn PDF document text
    • https://fibaquitaine.fr/cebatrama/userfiles/files/44980706161.pdfIn PDF document text
    • http://domgr11.ru/uploads/files/fekexuberavudupi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=free+printable+analogies+worksheets+3rd+gradePDF 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_off0000c85c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC85C 11140 bytes
SHA-256: fc43a37aaf3212cd8a69f96930d3049a818da7aee8539fe04425d7c4d2a4ad15
font_01_sfnt_off0000e1eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f9fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9FD 16972 bytes
SHA-256: 6f83aaa2faafec3839d51ad0860a7cd8d3a3a07fa6bc048068d789ead82cbcea