Malicious PDF — malware analysis report

Static analysis result for SHA-256 091a231ada308a48…

MALICIOUS

PDF

74.5 KB Created: 2021-09-11 11:19:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 4c690e2585e9ccb4eb47e4fa41e34f6b SHA-1: ebe90596ca1f24412699c34204ecbbb289f89312 SHA-256: 091a231ada308a482d932867b6a4dfb68fc4e82d56f72750cafc9954c2fb7d2b
126 Risk Score

Malware Insights

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

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 pointing to external sites, suggesting it functions as a link farm or a lure for phishing attacks. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically highlights the nature of these links, indicating a pattern of directing users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://svenjakretschmer.com/ckfinder/userfiles/files/wefoxix.pdf In PDF document text
    • http://dade666.com/userfiles/202109file/2021090411093770554.pdfIn PDF document text
    • https://elemental-ia.com/userfiles/file/pebijuzuxav.pdfIn PDF document text
    • http://vlajkylevne.cz/UserFiles/File/setalikutanoletumejupo.pdfIn PDF document text
    • https://queensflower.nl/clientfiles/naroronew.pdfIn PDF document text
    • http://montesantangelo.it/files/files/vifuro.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136fde224247---lajixuzetiw.pdfIn PDF document text
    • http://parejalecaros.com/adjunto/upload/fck/files/binoxafuk.pdfIn PDF document text
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/e1abb005d2072bbb16ac4327e03078d1/65700174058.pdfIn PDF document text
    • https://equator-maritime.com/userfiles/file/nejekodag.pdfIn PDF document text
    • http://xn--80aab8aioy.xn--p1ai/userfiles/file/60618636373.pdfIn PDF document text
    • http://imreelectric.sk/uploads/file/30562598854.pdfIn PDF document text
    • http://immobilieninvestors.com/userfiles/file/xaxepejox.pdfIn PDF document text
    • http://www.logistiekverbeteren.nl/ckfinder/userfiles/files/pugaxo.pdfIn PDF document text
    • http://ourgans.org/userfiles/files/velifazelanimazedodejot.pdfIn PDF document text
    • http://labonscafe.com/userfiles/8657032285.pdfIn PDF document text
    • http://szigmetal.hu/editor_up/gojememimino.pdfIn PDF document text
    • http://fujavietnam.com/images/Download/jutarijenokafus.pdfIn PDF document text
    • http://narcisse.sk/editor_uploads/files/zuxegamozipol.pdfIn PDF document text
    • https://hsdinstruments.nl/uploads/files/92173741148.pdfIn PDF document text
    • https://ensegun2.com/ckfinder/userfiles/files/xonazusamaju.pdfIn PDF document text
    • http://bestpokeya.com/uploads/files/66104958856.pdfIn PDF document text
    • http://cachnhietcacham.vn/Images_upload/files/29298164037.pdfIn PDF document text
    • http://sensi-leszno.pl/userfiles/file/57256506068.pdfIn PDF document text
    • http://opt-russtd.ru/data_center/upload_pictures/file/didudajesaxiralawapu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=8+ball+guideline+apkPDF 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_off0000bfe1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFE1 17524 bytes
SHA-256: b8094682ed7503b36aae190cef0e7f69ef318ed48881a2d1bb39360056185d61
font_01_sfnt_off0000ed22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED22 10524 bytes
SHA-256: 1eefccc1f45f7992ad8fe427b469151f933e796f22d2d74ebc56962507c40bae
font_02_sfnt_off000104af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104AF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1