Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca5100d3fc64b1cb…

MALICIOUS

PDF

80.1 KB Created: 2021-09-18 01:44:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 7b673dc5e3e1f46a8bddf1fc3f432f20 SHA-1: 4fdc7dcf6f0d4bd8a945a4026375e730dcebb4f7 SHA-256: ca5100d3fc64b1cb72efd9c19532a16d2dce5ff1b3149a960132f73abdd10ee4
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains numerous links to external websites, with several pointing to compromised WordPress upload directories and disposable hosting, suggesting a link farm designed to redirect users. The PDF structure and embedded links indicate an attempt to lure victims to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://pixomot.ru/uplcv?utm_term=live+foto+android PDF link annotation
    • https://www.area-tlc.com/public/ckfinder/userfiles/files/95820527129.pdfIn PDF document text
    • http://tsrmvolontari.it/userfiles/files/72094368735.pdfIn PDF document text
    • http://daydeothe.vn/rich_editor/file/21848623581.pdfIn PDF document text
    • https://profession-your-dr.com/uploads/files/202109061755585915.pdfIn PDF document text
    • http://ladyqueen.it/userfiles/files/veralizajusunidibusami.pdfIn PDF document text
    • http://nbc.ua/design/pic/file/50041519133.pdfIn PDF document text
    • http://www.enfersalus.com/ckfinder/userfiles/files/saxum.pdfIn PDF document text
    • https://total-sport.pl/img/upload/files/78015556397.pdfIn PDF document text
    • http://exito-opakowania.pl/userfiles/file/92959234237.pdfIn PDF document text
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/36268baed5dc6270b290d01b431f6c3b/44375785578.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/zajara.pdfIn PDF document text
    • https://www.anoregmt.org.br/ckeditor/ckfinder/userfiles/files/76927546801.pdfIn PDF document text
    • https://otoform.com/upload/ckfinder/files/pesowof.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/b4dfd03d2b1f2d05eedfd759561ba5aa/korekexemigerutotixu.pdfIn PDF document text
    • http://www.armstrongre.com/files/files/40274070315.pdfIn PDF document text
    • https://imagebrandstudio.com/userfiles/file/resosupeje.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/67103009449.pdfIn PDF document text
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/vfo848rpa0okmllvjmj44lir0h/7839281217.pdfIn PDF document text
    • https://volgogradexpo.ru/ckfinder/userfiles/files/72094522481.pdfIn PDF document text
    • http://contua.org/userfiles/file/pujazubugugudapiziwada.pdfIn PDF document text
    • https://larrialdiak.es/files/galeria/files/bafuwakepuza.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_off0000d5de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5DE 18256 bytes
SHA-256: 677de2dcac73d0113f7128ba037d37399b32d0eea05329d4d38c6740ca165445
font_01_sfnt_off000104c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104C0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011cd7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CD7 10156 bytes
SHA-256: 56bfdece10b78526898a7858237cd857e45ce5078df86cf7f757acac8f685682