Malicious PDF — malware analysis report

Static analysis result for SHA-256 ee84b6b6cc8cbc42…

MALICIOUS

PDF

80.4 KB Created: 2021-09-19 13:47:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 4bce40b3ed607fa2dbc2ef0cb1f3d3e1 SHA-1: f597e9a6769fd28dfc1ff564f0a0eb21fbecc3b7 SHA-256: ee84b6b6cc8cbc42be75a0cbd39a0028f29d92f38637c008d6c9f348478c89db
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by multiple heuristics, including a link farm detection and a machine learning model, indicating malicious intent. The embedded URLs and the PDF structure suggest it is designed to redirect users to potentially harmful websites. While no scripts were explicitly extracted, the nature of the PDF and its numerous external links point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://ketchas.ru/uplcv?utm_term=android+sd+exfat PDF link annotation
    • http://tortsurprise.ru/upload/redactor/files/57536365171.pdfIn PDF document text
    • http://polymer-optix.de/userfiles/file/lugananijojomoziji.pdfIn PDF document text
    • http://rentappli.com/tinymce/jscripts/tiny_mce/plugins/phpimage/phpimage/upload/images/file/47467885732.pdfIn PDF document text
    • http://tonghuichem.com/upload/files/71163642002.pdfIn PDF document text
    • http://alajwakh.com/uploaded_files/userfiles/files/15577992023.pdfIn PDF document text
    • http://kimdaiphatsteel.com/Images_upload/files/60800624650.pdfIn PDF document text
    • https://bibonatura.hu/ckfinder/userfiles/files/bazadelazukuminaralefe.pdfIn PDF document text
    • http://15441707.com/data/board/file/20210904082958.pdfIn PDF document text
    • http://nakloboucku.cz/uploaded/file/89405265279.pdfIn PDF document text
    • http://xn--80ab1a9a.xn--p1ai/sadm_files/34408750056.pdfIn PDF document text
    • http://clinicaveterinariaalbese.eu/userfiles/files/77940106045.pdfIn PDF document text
    • https://angelsolutions.ro/ckeditor/ckfinder/userfiles/files/gunixogutinidejepipos.pdfIn PDF document text
    • http://domesticsolutionsagency.com/userfiles/file/nulidinakimubane.pdfIn PDF document text
    • http://castudio.eu/userfiles/files/jowevapuzekadedujasomirew.pdfIn PDF document text
    • http://maydemtienvn.com/upload/files/16263149110.pdfIn PDF document text
    • http://news-hk.net/uploadfile/file///lezefidusazogo.pdfIn PDF document text
    • https://perfecthospital.net/ckfinder/userfiles/files/bijudapozekemogegenoxigos.pdfIn PDF document text
    • https://tlkingatlan.hu/kepek/other/file/36729732975.pdfIn PDF document text
    • http://studiomistretta.com/userfiles/files/99720025806.pdfIn PDF document text
    • http://beijingteye.com/upload/files/sibujebijovuvatowidogak.pdfIn PDF document text
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ed88e6d5a9---javadegoxopukadekufavu.pdfIn PDF document text
    • https://torbay.ru/images/uploads/file/fokevedado.pdfIn PDF document text
    • http://anm-av.de/uploads/files/76855253825.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/77614802955.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://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_off0000db5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB5D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f36f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF36F 17204 bytes
SHA-256: bb3dd37adb95eb84f77b727a15f3a1b729a59debdf16c93e1f1e551a90ee0854
font_02_sfnt_off0001200a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1200A 10384 bytes
SHA-256: 1c341c6716ebe1ac3fbb7472ab31a22c2c028dd8e664428bef2e9cc085239939