Malicious PDF — malware analysis report

Static analysis result for SHA-256 55c9267f54413055…

MALICIOUS

PDF

93.2 KB Created: 2021-07-01 13:19:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 5cd49df43229c6820a7645f69d150b18 SHA-1: da244d77f5da48278bafcb4d69e30495878e57fe SHA-256: 55c9267f544130559df62d1f42553a3858db08c040abdc1854a37aa1a1b8895b
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It functions as a link farm, containing numerous URLs pointing to compromised WordPress uploads and other disposable hosting sites. The embedded URLs suggest an attempt to direct users to potentially harmful content or phishing sites, aligning with a spearphishing attachment attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://laborke.ru/uplcv?utm_term=matrix+multiplication+calculator+with+variables PDF link annotation
    • https://pmeds.us/userfiles/file/janulonipinibupemise.pdfIn PDF document text
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606d5086371cc---goxitiruvoropagejidolewi.pdfIn PDF document text
    • http://abc-tel.ru/data/File/25633915003.pdfIn PDF document text
    • http://chi-kara.net/userfiles/file/wijexikitajumenonule.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/s2drr0v8eejs1k53m7fckfcjo6/15209551982.pdfIn PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/e77182be6f8714d928e4d623a13ae25d/63096814127.pdfIn PDF document text
    • http://bbpcosmetics.com/admin/upFiles/2021-6/file/84987032562.pdfIn PDF document text
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/63958a620539bf6d1c6fb68167d725b3/fizasefajodufef.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608e9b4ed50c9---99095995908.pdfIn PDF document text
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/660ecbdf181f733a0f1900ed67e07cbd/90845621030.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160c0670a79fe2---8780084680.pdfIn PDF document text
    • https://abhimaninteriors.com/ckfinder/userfiles/files/14207514245.pdfIn PDF document text
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607e0842d3fbb---63594479204.pdfIn PDF document text
    • http://www.phuongdonggolf.vn/app/webroot/uploads/files/mokidizisozofi.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/16077dc59c454c---25426200465.pdfIn PDF document text
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/4f824e6e3ac28450feddd1bd720782a0/sikujivisu.pdfIn PDF document text
    • https://www.jscorporation.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/1608fe0171bb05---jipezobaxepig.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607270545499f---wuvikek.pdfIn PDF document text
    • http://workprohealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d1bf4d6f59---valusivoxoxewubed.pdfIn PDF document text
    • http://soft-pro.hr/upload/datoteke/63270576674.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/5bedfeb4013ec64441e049c23cf88520/29642816693.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bfb2caa426d---jugolefex.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/16077a950e4bfc---66668013996.pdfIn PDF document text
    • http://alkanboya.com/files/file///xotekijegikujinikolesusal.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_off00010589.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10589 11124 bytes
SHA-256: aae2f6fe8d5ece776411e073ebe8ea570ec94b725890f8dbb9e1db23f4b5eb31
font_01_sfnt_off00011f2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F2B 17976 bytes
SHA-256: c1982528eb26947f6747c5a19722d4833890b4af04e9e1141f0a00fce83f0961
font_02_sfnt_off00014ef3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14EF3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1