Malicious PDF — malware analysis report

Static analysis result for SHA-256 bce5ac26de149863…

MALICIOUS

PDF

93.7 KB Created: 2021-09-06 05:05:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: ce9219b8877ecfa4aaa5c2cec5d5c882 SHA-1: 23399b7ab10acc12793e015ecbd7bd02aea9114d SHA-256: bce5ac26de1498632774f51fc3d44bcd43a81ac8dcd7873b67c7fcc363f1af54
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with many URLs pointing to compromised WordPress upload directories, suggesting a phishing or redirection scheme. The document body is heavily obfuscated and contains no readable content, further supporting its role as a malicious container.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a74a2e1fd28---xajedawuweporobigigabujo.pdf In PDF document text
    • http://www.armstrongre.com/files/files/fevisoxopasoba.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160d053f3ed09e---82935300084.pdfIn PDF document text
    • http://uro-medical.pl/zdjecia/fotki/file/kupolu.pdfIn PDF document text
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16093ce6f54184---50710705849.pdfIn PDF document text
    • https://www.casestilistas.es//ckfinder/userfiles/files/lorepapu.pdfIn PDF document text
    • http://jp-cable.com/d/files/45819060363.pdfIn PDF document text
    • http://carnavaldemarbella.com/Senegal_5/Content/files/userfiles/file/57261622622.pdfIn PDF document text
    • https://blagoustroystvo24.ru/ckfinder/userfiles/files/74745588417.pdfIn PDF document text
    • https://baileyelectrical.services/wp-content/plugins/super-forms/uploads/php/files/9jtos47f6t56sg6aeanm4uuc4s/tinepixuwapixalofizilobo.pdfIn PDF document text
    • http://tokyoracing.hu/userfiles/file/kizinemejorole.pdfIn PDF document text
    • http://zonwering-belgie.com/ckfinder/userfiles/files/69670218259.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160f5231d046be---nogolonenutenodetexok.pdfIn PDF document text
    • https://www.heracles-hotel.eu/wp-content/plugins/super-forms/uploads/php/files/q27bro0cto8qmvif7tgfa5h6fv/87607369145.pdfIn PDF document text
    • http://52fotki.ru/ckfinder/userfiles/files/xamut.pdfIn PDF document text
    • http://xn--80ahcjevtqq.xn--p1ai/ckfinder/userfiles/files/fudilele.pdfIn PDF document text
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092f451bb299---jibozi.pdfIn PDF document text
    • http://ohana1bbq.com/uploads/files/93503958917.pdfIn PDF document text
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/cff63758f0cd0e0b1055370742e1844c/30759452153.pdfIn PDF document text
    • http://dailitara.lt/bites/uploads/file/dazonoxusekelejadovox.pdfIn PDF document text
    • http://abbwingslynnhaven.com/uploads/files/jejaxivilonuwexunurelej.pdfIn PDF document text
    • https://www.finestkindcharter.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607375f539900---3481354502.pdfIn PDF document text
    • http://apexnepaltravel.com/userfiles/file/dezasisapumatunasewom.pdfIn PDF document text
    • http://amblesidewindermere.ca/fckuploads/images/file/puteni.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16105a96361aef---36277341025.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=the+postnational+constellation+pdfPDF 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_off00010477.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10477 19508 bytes
SHA-256: 7636259971e13ab5d6dd2a048af7253934e9b88bb84c5485bf7b25eddc07330c
font_01_sfnt_off000136fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136FB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014f12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14F12 10580 bytes
SHA-256: f40d0fd9aa3adf0d5a9c22ae3af86402e4b1472703ef5662cbab3ce11dbf5081