Malicious PDF — malware analysis report

Static analysis result for SHA-256 71ef4a8570c5dfc7…

MALICIOUS

PDF

76.2 KB Created: 2021-09-14 02:12:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 2e090d6a19dfa3b2e7f31ee34f6391b0 SHA-1: 47ef8df1b6b90bef174a1c5fd0c2c9ae116a3c0a SHA-256: 71ef4a8570c5dfc7508a17b7c7e9b50fa7470ce082219618f80fc8e67b60aecd
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, with one specifically identified as a link farm on disposable hosting, suggesting a phishing or redirection scheme. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards a malicious document designed to lead users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://paymentor.nl/uploads/file/pudogoralizunetedorapox.pdf In PDF document text
    • http://santamariamikado.com/uploads/files/49541149454.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/0elhmc0pl1gk52f6aj7hoe91c5/17071050334.pdfIn PDF document text
    • http://news-hk.net/uploadfile/file///11550139445.pdfIn PDF document text
    • https://chataigne-cevennes.fr/imgs/files/jigetamediji.pdfIn PDF document text
    • https://dukra.sk/editor_uploads/files/68191807143.pdfIn PDF document text
    • https://pharma-tools.eu/galeria/file/33259130586.pdfIn PDF document text
    • http://pogotowienaukowe.com/Upload/file/9733767377.pdfIn PDF document text
    • http://tsnpharma.com/upload/files/jisojefo.pdfIn PDF document text
    • https://taxforce.nl/userfiles/files/11188012511.pdfIn PDF document text
    • http://jfe.hk/userfiles/vevawevozuvesurikexub.pdfIn PDF document text
    • http://ohadalegistrocbarter.com/ckeditor/uploads/files/19380426491.pdfIn PDF document text
    • https://edarky.net/data/file/71874454647.pdfIn PDF document text
    • https://songod.vn/uploads/image/files/9230833332.pdfIn PDF document text
    • https://rheinfurth.de/userfiles/file/xebojinudumemudosula.pdfIn PDF document text
    • http://onmamtour.com/FileData/ckfinder/files/20210911_922030744D5253E7.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613a03f2d4d52---tatamigepifodimebi.pdfIn PDF document text
    • http://turar-mussin.com/userfiles/File/45262375429.pdfIn PDF document text
    • http://avandcie-automation.com/ckfinder/userfiles/files/74384672681.pdfIn PDF document text
    • http://eiak.org/upload/editor/files/7639498715.pdfIn PDF document text
    • http://on-video.com/movies/movie_data/file/28485954391.pdfIn PDF document text
    • http://youzedu.com/ckimages/files/20210911205259146911.pdfIn PDF document text
    • http://aromata.ru/upload/files/62987308661.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=harga+hp+android+sekenPDF 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_off0000c9ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9AD 10608 bytes
SHA-256: 430886b4ffc5b4268c30a96f7b17bcab652c6a5a88a5b77d972d0e39d00c4f54
font_01_sfnt_off0000e18a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE18A 16112 bytes
SHA-256: 92211f8c89d18d1c98deb8ce86c9875be4b9e238055815af6a22c4483b5decdc
font_02_sfnt_off00010b2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B2D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1