Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac770247fccac8d4…

MALICIOUS

PDF

73.0 KB Created: 2021-06-13 08:14:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: ce0cac5fadc0e554039a2a65bef2d205 SHA-1: e4f151a3c20d078a0fa0387e06d6730ff4b9cab1 SHA-256: ac770247fccac8d4f9c4e680a8bfad855aee8ff34352d65ec4546f9f8de549a1
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://wastran.ru/uplcv?utm_term=bank+reconciliation+format+in+excel PDF link annotation
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/fe75421f23479a4b397b59918551608c/36282598521.pdfIn PDF document text
    • http://occahomesearch.com/userfiles/files/86780204334.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607af0fd3ee9f---89780747091.pdfIn PDF document text
    • http://asupuro.com/user_data/image//file/dojuliradajunezes.pdfIn PDF document text
    • https://salvamontbihor.ro/app/webroot/files/userfiles/files/81425363419.pdfIn PDF document text
    • http://azizolace.cz/images/file/96851298470.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607adab893457---zogumamadiza.pdfIn PDF document text
    • http://andlupa.com/userfiles/file/gasogeriduxo.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607ad32ce3279---84963427419.pdfIn PDF document text
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/d673b6629fbd6b0ceda43c5f2a3d960d/vujanokuvuvesilekapem.pdfIn PDF document text
    • https://www.harasportcenter.com/wp-content/plugins/super-forms/uploads/php/files/9q48tnscpu80g15o1j6s89glv3/baroj.pdfIn PDF document text
    • https://www.amiunaorchestra.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c58b21d2232---polokujeseluboxurer.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16089b112375d9---lazikuwawej.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607097463228a---34377249796.pdfIn PDF document text
    • https://meesens.be/KrMee/Tekstverwerker/gepatimerazidozer.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/fa0574ee9e6c16f5ee0dc33c71803037/67760155395.pdfIn PDF document text
    • https://www.freshstartdigitalmarketing.com/wp-content/plugins/super-forms/uploads/php/files/7eac0749dd009917ff156ecedfb3dbcc/70057784307.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e49f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE49F 5032 bytes
SHA-256: 0cfdebdfa9ad86bf4616474c44cc27f88a4f356a15952c1da42c5533041fab81
font_01_sfnt_off0000f5af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5AF 9832 bytes
SHA-256: 35e96b5ca60dbd594239aedd58e0e78487cd7c195091e72341939a2acee7c777