Malicious PDF — malware analysis report

Static analysis result for SHA-256 33ad893038e9e3cb…

MALICIOUS

PDF

96.2 KB Created: 2021-07-15 12:06:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 67c03860f8a32429d32fb43d43e4ba44 SHA-1: 154126af0c776e28f220f853fae4b8cf7d228611 SHA-256: 33ad893038e9e3cbdc808a521f35b8ceb8eb250e6f844da874df999cf1281c35
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a ML classifier and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs pointing to compromised WordPress upload directories and other potentially malicious sites. The primary purpose appears to be directing users to external, compromised resources, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

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://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a92a7b9f946---57721929336.pdf In PDF document text
    • https://thejasmineway.net/wp-content/plugins/super-forms/uploads/php/files/vvs34q2vfh9927i3p43pkud3tp/69560011427.pdfIn PDF document text
    • http://alarcon-v.com/editor_upload_image/file/baxodobamipef.pdfIn PDF document text
    • http://ne-moloko.ee/wp-content/plugins/super-forms/uploads/php/files/5545f6fd970240378cb973b17c76e994/jaluxeludelimuw.pdfIn PDF document text
    • https://kogan-photo.ru/wp-content/plugins/super-forms/uploads/php/files/5833b91cda05c7290771c7f2a28ba64e/vowiwurisipakediloropi.pdfIn PDF document text
    • http://coimbra.hu/uploads/ckfinder/userfiles/files/55744275050.pdfIn PDF document text
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/94e72ed6f2eac49098c6d1fe7e471c2a/29488383240.pdfIn PDF document text
    • http://sys-svinding.dk/userfiles/file/17600700525.pdfIn PDF document text
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/d7e1087f56abf978868f04a7ce77273b/99910530804.pdfIn PDF document text
    • http://chaitraglaze.com/uploads/32196393849.pdfIn PDF document text
    • https://xistenze.com/files/files/9800003298.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16083c570555d1---jojutipizunokanum.pdfIn PDF document text
    • http://angelcabrera.com/FCKfiles/file/bunijal.pdfIn PDF document text
    • https://frontlinetherapist.com/wp-content/plugins/super-forms/uploads/php/files/55d47757daf7c6445af9e039528d6653/6337522222.pdfIn PDF document text
    • https://cecprint.com/images/file/kevakitodiro.pdfIn PDF document text
    • https://www.glasswindowequipment.com/wp-content/plugins/super-forms/uploads/php/files/e36ee14bf4cd91fbf748d50cd7a041a4/xizone.pdfIn PDF document text
    • https://pensiuneavalentina.ro/app/webroot/file/36050680510.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/0519aae66e7e574e6826e89f5bd91f88/782726549.pdfIn PDF document text
    • http://hopkinshigh62.com/clients/7/77/7764523e397120ad9b09b1da26998858/File/bitoji.pdfIn PDF document text
    • http://brenno-tojestto.pl/userfiles/file/migigedemibupa.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/160d64317c25c2---18344538467.pdfIn PDF document text
    • https://www.gasserbush.com/wp-content/plugins/super-forms/uploads/php/files/797ab4351689dc84c97c65dc1659c30c/taragujes.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=letter+a+in+hangulPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000101ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101AE 5548 bytes
SHA-256: 1d628953c3d083c89cd48fff42a6cf0cfc3b9fec4bc4a5802a9ca9b1bd07926c
font_01_sfnt_off00011478.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11478 10156 bytes
SHA-256: da169fedcb350c8cdd55e6facfffc0b02d30a8de744499fec4932d23444e47ba
font_02_sfnt_off00012b05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B05 18424 bytes
SHA-256: 864cf87ab9cce6807eaa590170754fc9f8eab453d1165f79f6c956a070f9dcd2
font_03_sfnt_off00015b3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15B3A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1