Malicious PDF — malware analysis report

Static analysis result for SHA-256 88fcd9661e59dcd5…

MALICIOUS

PDF

69.0 KB Created: 2021-06-12 11:26:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: feceb68408994cd06a6e6226f1e020e0 SHA-1: a96ba9b8b08efaa49c9c1deea2685005c9a432b5 SHA-256: 88fcd9661e59dcd5a9e39a04b3dee6629ecf54dab7292ed5bf1499a6da700b37
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains multiple links pointing to compromised WordPress sites, suggesting an attempt to host and distribute malicious content. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for link farms, often associated with phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to deliver a second-stage payload via the embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://medvor.ru/uplcv?utm_term=excel+sheet+backtesting+download PDF link annotation
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/7495885441473cd1decdaff27c041261/11127418155.pdfIn PDF document text
    • http://youngshiny.com/userfiles/file/1622236559.pdfIn PDF document text
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b80afa32e09---44757232681.pdfIn PDF document text
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/c2a9c305328f058a1bdc99fb22afc383/2067583226.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/16084f07878899---94023308772.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160759dd530a29---ponixolemopap.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/87462981341.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b591faf7a6---guwatisesivatagive.pdfIn PDF document text
    • http://highendschmiede.de/highendfiles/file/zanujebokobubave.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b25944edbd---xonebubumavi.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160afb3f8309df---52469497065.pdfIn PDF document text
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080ae685ab38---vutimurogapixodupago.pdfIn PDF document text
    • http://bjaimama.com/data/upload/2021/05/file/202105110517415671.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/nkudmh2l9ja6uo4bhnjiufe0q2/nubafutewusodadawuruw.pdfIn PDF document text
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/311909fbc579d8870e35490a8e3bbcfc/zulefowexilutoz.pdfIn PDF document text
    • https://mmszke.hu/files/file/8000264245.pdfIn PDF document text
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbae0e7112---punafub.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_off0000d184.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD184 5424 bytes
SHA-256: 37f94b24668417dd1a292d334e2c2228405302e4e497c9b1ac5278d4aa94227f
font_01_sfnt_off0000e40e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE40E 10264 bytes
SHA-256: 2e199fff2d5682464ccd39060d9ee777ed1a1d71b55ebc17a2f2bc0de338d55f