Malicious PDF — malware analysis report

Static analysis result for SHA-256 3df6863b261f8ba6…

MALICIOUS

PDF

89.4 KB Created: 2021-10-09 16:18:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 8ef38292bc4cf0028cb813ea2846fc8a SHA-1: 8e594dc1b5cda080ea867de0c3d8f16a0fc372c2 SHA-256: 3df6863b261f8ba6c1178f15d10ea6b6d07504b7bda95f1c59f5abe534de05f9
156 Risk Score

Malware Insights

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

The sample was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains numerous external URIs and link farm patterns pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution attempt. The document body is unreadable, but the presence of link farms and external URLs strongly indicates an intent to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://allytemp.ru/uplcv?utm_term=baby+girl+arrival+wishes PDF link annotation
    • https://nnt52.ru/userfiles/file/nufigumevalodeleva.pdfIn PDF document text
    • http://ridendo.cz/files/file/8124314321.pdfIn PDF document text
    • http://cokhixnktientien.com/Images_upload/files/vojaparag.pdfIn PDF document text
    • https://ariconium.cz/webpagebuilder/ckfinder/userfiles/files/rofowugajivitemenosu.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/16134888a5d74f---zefizovatuturat.pdfIn PDF document text
    • http://urotunisia.com/uploads/FCK_files/file/buvesep.pdfIn PDF document text
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/363b24ca510c6adb2da42e0bcf1cbf28/58613051029.pdfIn PDF document text
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614785bf3ba9d---43138687732.pdfIn PDF document text
    • https://sabresources.com/FCKuploads/file/sagonu.pdfIn PDF document text
    • http://odnoklassniki-files.ru/images/uploads/files/zovumikoxas.pdfIn PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/1fcd89ba660ec762fd7c3b371b6796f6/51899077232.pdfIn PDF document text
    • http://ristoranteibucanieri.it/userfiles/files/rofoxojenarasumu.pdfIn PDF document text
    • https://redengewinnt.com/userfiles/file/92554068095.pdfIn PDF document text
    • http://musicfriend.vn/public/default/ckeditor/files/kirufe.pdfIn PDF document text
    • http://chekeeh.ir/basefile/chekeehir/files/14124036499.pdfIn PDF document text
    • http://urbancollab.com/userfiles/Proj_Name/files/82321731953.pdfIn PDF document text
    • http://meyergarden.com/ckfinder/userfiles/files/32657914893.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614df315afa3d---90763806877.pdfIn PDF document text
    • https://creativitagh.com/pevron/www/img/file/mafevegepuvofobekorivan.pdfIn PDF document text
    • https://raguvosbaldai.manovonia.lt/images/files/66784840139.pdfIn PDF document text
    • https://weboonline.com/ckfinder/userfiles/files/maweregita.pdfIn PDF document text
    • https://weblative.com/wp-content/plugins/super-forms/uploads/php/files/32qolo5r4noe0ve678jb4sqdot/31097971042.pdfIn PDF document text
    • http://kokocurry.gm/userfiles/file/xugagukixisu.pdfIn PDF document text
    • https://biocoils.com/img/file/74983284281.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_off0000f56c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF56C 19328 bytes
SHA-256: ffc3d6f27850770b72a14c74f1e89e7e2970df9505d840fc94b7ec7bb1932f8d
font_01_sfnt_off0001279e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1279E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013fb5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13FB5 10524 bytes
SHA-256: 9948dcb0612f76b1eb1e2dc61a08831bcd2ffcb764405df1b2d195c5fbe45a4e