Malicious PDF — malware analysis report

Static analysis result for SHA-256 f658f46f6e9cfd87…

MALICIOUS

PDF

69.5 KB Created: 2021-10-03 15:57:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 485fb77f12a0b5beb7acf3d0f47fe75e SHA-1: ff3a6b129f84f411c1cab1c127766d69ee926142 SHA-256: f658f46f6e9cfd87d5f57d6bc8a59335a8b1cc3c4a84ae07c1ab35465293165a
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier. Heuristics indicate it functions as a link farm, with multiple URLs pointing to compromised WordPress sites and disposable hosting. The embedded URLs and link farm structure suggest an attempt to direct users to malicious content, likely for phishing or malware delivery.

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://laborke.ru/uplcv?utm_term=sentence+about+however PDF link annotation
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/5e4a2e95621b4d6c7b89377f195470da/25624351583.pdfIn PDF document text
    • http://no1sushinroll.com/uploads/files/45637606976.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/luanvcdgm6mq2ng1uas854enh3/piletijawawamibum.pdfIn PDF document text
    • http://czyxchem.com/upload/files/kawiwu.pdfIn PDF document text
    • https://mvmdigital.gr/files/files/zudufikanizunadasi.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/55816511374.pdfIn PDF document text
    • https://toppelletmachine.com/d/files/89034904783.pdfIn PDF document text
    • https://solelane.com/ckfinder/userfiles/files/wimipojimogutidel.pdfIn PDF document text
    • http://keifo.ru/ckfinder/userfiles/files/75078947082.pdfIn PDF document text
    • https://fasaac.org/temp/files/wadopur.pdfIn PDF document text
    • https://rockyhotelsgroup.com/uploaded/files/2219884554.pdfIn PDF document text
    • http://urgentcarepb.com/userfiles/file/tifanawilavesageguz.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/161316e7fbb311---dezidugevuzituxaluvanida.pdfIn PDF document text
    • https://synersys.fr/contenu/file/47920914602.pdfIn PDF document text
    • https://firsatpin.com/calisma2/files/uploads/natinu.pdfIn PDF document text
    • http://nowyhotelik.pl/userfiles/file/pumorafizumumevenepa.pdfIn PDF document text
    • http://korsorlampang.net/user_img/files/14412472638.pdfIn PDF document text
    • http://zjleiou.com/images/upload/File/sininomedolite.pdfIn PDF document text
    • https://essaidafm.com/uploads/FCK_files/file/nivajufipulijan.pdfIn PDF document text
    • http://csim.jp/ckeditor/uploads/files/dalogosuxagafonepuwiw.pdfIn PDF document text
    • http://zeguvietnam.com/uploads/ckfinder/files/neradirud.pdfIn PDF document text
    • http://kenshopvn.com/uploads/files/meriramefelixet.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613b9fa8084a4---36772288277.pdfIn PDF document text
    • http://erainbowrealty.com/userfiles/file/37393903738.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_off0000b15b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB15B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c96d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC96D 15420 bytes
SHA-256: 557696ffa0ac2eb24d3a9047e92a84b5c24860ca542832284e16dc26f16b5d47
font_02_sfnt_off0000f092.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF092 10488 bytes
SHA-256: 31f58ae72c9b5683587b27151889d2026ade9021cb89c743705916caa97f1058