Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a89b3942134bdbb…

MALICIOUS

PDF

68.2 KB Created: 2021-09-27 07:33:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: c0b3ca41ea4db3245073153b72a020f1 SHA-1: 10fb4b10602dcb8cc4894393e712c0bdae9c9edc SHA-256: 8a89b3942134bdbb9f1ad06c2546848e4af85ae20fc5c85e76d8258472f3082f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Numerous heuristics point to the PDF acting as a link farm, directing users to various external URLs, some hosted on compromised WordPress sites. The presence of external URI links and link farm indicators suggests the primary purpose is to redirect users to potentially malicious content, aligning with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://smidgel.ru/uplcv?utm_term=material+tab+layout PDF link annotation
    • http://zhouzhuank.com/v15/Upload/file/2021923156184396.pdfIn PDF document text
    • https://akemi.ro/hirek/file/fozexubolubapute.pdfIn PDF document text
    • http://annabarons.com/files/files/kivixuxijolusogurokafav.pdfIn PDF document text
    • https://ecableapp.com/FCKeditor/FCKimgUpload/file/7707545322.pdfIn PDF document text
    • http://konferencii.org/web/uploads/assets/file/duzimexodogikateguvimi.pdfIn PDF document text
    • https://medosojewellery.com/userfiles/files/jevakofav.pdfIn PDF document text
    • http://softwarefactory.nl/images/file/kopege.pdfIn PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137da1700439---22384483068.pdfIn PDF document text
    • https://tpijobportal.com/ckeditor/ckfinder/userfiles/files/lisixad.pdfIn PDF document text
    • http://mtcongnghiepxanh.com/upload/fckimagesfile/nabiwado.pdfIn PDF document text
    • https://bdlvn.com/steel/upload/files/12696105737.pdfIn PDF document text
    • http://scandirent-new.ru/uploads/assets/file/zomapuro.pdfIn PDF document text
    • http://matsusushionline.com/uploads/files/76144988298.pdfIn PDF document text
    • http://juha.be/_files/file/pibowibu.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16139d2b918bc8---fifodiremuvoviwafu.pdfIn PDF document text
    • http://udaybharat.in/ckfinder/userfiles/files/61849142394.pdfIn PDF document text
    • https://pilot-nav.com/ckfinder/userfiles/files/nawesuxofogidaxuj.pdfIn PDF document text
    • http://ingatlantv.tv/userfiles/files/95374688318.pdfIn PDF document text
    • https://33mobility.net/uploads/files/31805135066.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/f3d3b2522bae83f5746ed7828e952ff2/70229446141.pdfIn PDF document text
    • http://stjconsulting.it/userfiles/files/17690643436.pdfIn PDF document text
    • http://www.mostex.sk/files/articles/file/malegimafumep.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_off0000aef7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAEF7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c709.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC709 14832 bytes
SHA-256: aeb3d9e2e5e1c652d9c19a9a463cbd9b3850e568e1fd5df9a17aaf1e2f4fb3bd
font_02_sfnt_off0000eca9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECA9 10176 bytes
SHA-256: 4cf1503344a6d6ce4e028ba799eaeef378404f360ccbb2e190ee0a0113d32b35