Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f00c8dfe117a04e…

MALICIOUS

PDF

75.8 KB Created: 2021-10-05 17:27:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 2ae04555d051d918b8eb97c22ed4c847 SHA-1: 7e1e93c4fc381c001c494b19383ae5e67d711eb2 SHA-256: 8f00c8dfe117a04e40f311cf24769e709d06a414649d5756d4de2c734585ff83
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. Heuristics identified it as a link farm with numerous external URIs pointing to disposable hosting, suggesting a phishing or malware distribution scheme. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically flags the document's structure as a non-clustered link farm on disposable hosting, reinforcing the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://laborke.ru/uplcv?utm_term=the+castle+streaming PDF link annotation
    • http://visit-pune.com/userfiles/file/15325564693.pdfIn PDF document text
    • http://budaikepkeret.hu/uploads/file/rolugegikukudosewexinubor.pdfIn PDF document text
    • https://habibitours.org/ckfinder/userfiles/files/38243443115.pdfIn PDF document text
    • https://dongciao.com/uploads/files/202110030043335278.pdfIn PDF document text
    • http://cleversystems.ru/userfiles/file/51531938354.pdfIn PDF document text
    • http://rkenterprisesonline.com/FCKeditor/file/zujino.pdfIn PDF document text
    • http://kargo-box.com/uploads/files/tebajusomagezilag.pdfIn PDF document text
    • https://yocarbroker.com/upload/ckfinder/files/zemozelegunuvovalago.pdfIn PDF document text
    • http://st-ark.it/userfiles/files/10017071499.pdfIn PDF document text
    • http://bollnas.boj.se/uploads/userfiles/files/fapuwawimidozaxaru.pdfIn PDF document text
    • http://irinka.org/ckfinder/userfiles/files/ropatuvubotinafozetanuri.pdfIn PDF document text
    • http://architettorobertafasola.eu/userfiles/files/komeletowe.pdfIn PDF document text
    • http://mawarids.org/mpfiles/file/91925443135.pdfIn PDF document text
    • http://bayzones.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/96203286509.pdfIn PDF document text
    • http://ventexevent.se/uploads/file/gepufuluf.pdfIn PDF document text
    • http://robertoantoniz.com/resources/original/file/12249489930.pdfIn PDF document text
    • http://arcomproltd.com/userfiles/file/masogotunefamob.pdfIn PDF document text
    • http://tndgdemo2.com/ckfinder/userfiles/files/65143296174.pdfIn PDF document text
    • http://tele-klass.ru/i/upload/files/41889584149.pdfIn PDF document text
    • https://bikidi.com/UpFiles/WebEditorFiles/file/rixekasu.pdfIn PDF document text
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/a577e58a650c5bc7e19128c9c223de01/19350858390.pdfIn PDF document text
    • https://limpiezasinasel.com/userfiles/files/29499075926.pdfIn PDF document text
    • http://mengnuanua.com/app/webroot/files/files/rofamuvovigafodinubi.pdfIn PDF document text
    • http://kyea.org/imageuploads/19359644463.pdfIn PDF document text
    • http://pointerboards.com/uploads/admin/files/82278249991.pdfIn PDF document text
    • http://safaraval.com/basefile/safaravalcom/files/39378906896.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_off0000c77a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC77A 16648 bytes
SHA-256: 5e2dbca9cd5431f97d6d7f90901e1468de3a262416c705f8383bc4b7600d0efe
font_01_sfnt_off0000f202.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF202 10520 bytes
SHA-256: 087619e22a22d9c6619db9d70e3acc6c70aba1369b479f9237876f4119b26abd
font_02_sfnt_off000109c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1