Malicious PDF — malware analysis report

Static analysis result for SHA-256 5d1fedbd5594fb27…

MALICIOUS

PDF

70.9 KB Created: 2021-09-02 16:55:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 6efb7b985d59a7f59b445c1b6b77b2ca SHA-1: 7583be50a07d5711b48a3d0e482c180ce6d03ff4 SHA-256: 5d1fedbd5594fb275494d55a24d24e1a18229ee44d53327dc24bb6ffb00efd87
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple compromised WordPress sites and other disposable hosting. The presence of external URIs and the overall structure suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/6ghpqg4i6u48uducd666mskk81/gixewevoma.pdf In PDF document text
    • https://bitree.com/ckfinder/userfiles/files/47227714146.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160840e45db8a4---75737467027.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/6243ee399383f35ccea2eb128d876524/15816268875.pdfIn PDF document text
    • https://allianztc.ro/files/file/sazonifofomusatenurow.pdfIn PDF document text
    • https://synersys.fr/contenu/file/72121545622.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c29eb415e0a---zatezarupepatetobolin.pdfIn PDF document text
    • http://clarksville.net/wysiwygfiles/file/78984882322.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/161092b6e1cab5---6896777619.pdfIn PDF document text
    • https://jmtours.co/aym_image/files/78546074080.pdfIn PDF document text
    • http://naturallabs.fr/userfiles/file/10556800821.pdfIn PDF document text
    • http://xinxinhouseware.com/uploadfile/files/mulokexetafitixap.pdfIn PDF document text
    • http://ural-resyrs.ru/data/file/404711509.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/16083bee9c7dd0---1876157118.pdfIn PDF document text
    • http://ithaca1962.com/clients/41687/File/vakifukezupel.pdfIn PDF document text
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608119b61451b---88726152409.pdfIn PDF document text
    • https://krimgranit.ru/wp-content/plugins/super-forms/uploads/php/files/a2c2f1d872f9709dec7f8ca1df1c8987/39868511180.pdfIn PDF document text
    • http://brain-sh.tw/upload/file/45313774902.pdfIn PDF document text
    • http://growourworld.com/clients/83159/File/xasekuvasudovu.pdfIn PDF document text
    • http://dzstock.com/Upfiles/file/memalemotamawe.pdfIn PDF document text
    • http://russkiivopros.com/images/FCKeditor/file/lopitedupolusirujizevovav.pdfIn PDF document text
    • http://poslovniimenik.net/firme_data/files/92367347549.pdfIn PDF document text
    • https://roweryelectra.eu/app/webroot/uploads/file/16258143386188.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=ultrashort+pulse+laser+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_off0000b4f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4F3 16044 bytes
SHA-256: 0d658ffc5f93dceaaec9485d06dc6126e7feb8d95cda512025b7bf488d58bdd0
font_01_sfnt_off0000de2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE2B 10504 bytes
SHA-256: 2f6d2aaeeb64ccf33c6c582086c1e277aeef8d2b6fab821097c7d7a926ed42c3
font_02_sfnt_off0000f63a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF63A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1