Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6504efdf3c85614…

MALICIOUS

PDF

68.8 KB Created: 2021-06-22 23:28:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 80657d0e687a5e0604c77cd8a791b101 SHA-1: e566b53e8bf5e2ec48823b03843f83337ae37ac3 SHA-256: f6504efdf3c85614b7c2722e6d3d2fb2f0f5b4b2e3a7d631b3d1f4a11bd700af
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple compromised WordPress sites and other unknown domains, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://srp-galabau-rostock.de/wp-content/plugins/super-forms/uploads/php/files/3tb8ant0hi65noep74bpqp2j36/rijaj.pdf In PDF document text
    • http://stroisvias.ru/userfiles/file/maxifaxi.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210508085440551.pdfIn PDF document text
    • https://groupunsur1.com/contents//files/temelaruto.pdfIn PDF document text
    • http://jorkurojus.com/userfiles/file/fajowaduwavekumuzumivanij.pdfIn PDF document text
    • https://eobliecky.sk/userfiles/file/kozisavox.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/47a06q8mm27jo55dphtg2tce26/839473904.pdfIn PDF document text
    • https://bosgo.mn/uploads/files/wutogasuj.pdfIn PDF document text
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/54ft5b6v310r6196c1kppsj4kh/tejojijukeninazasu.pdfIn PDF document text
    • http://www.molinoag.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7a0c898af8---gexamemamerogefuj.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad43a2c2665---rowit.pdfIn PDF document text
    • https://takeorders.online/wp-content/plugins/super-forms/uploads/php/files/eh2ibep29j0u9ga9ppi7g1hnep/22532339539.pdfIn PDF document text
    • http://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1607fdeaf22ced---sixagebadiziragiwo.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/flku5dsd81vd0t2a7dpla1lv1t/vujavagagivewom.pdfIn PDF document text
    • http://bestapp4u.com/admin/uploadedfiles/file/kusula.pdfIn PDF document text
    • https://betenagro.com/sites/default/files/file/16939587382.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=pdf+lean+six+sigmaPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c2a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2A8 5200 bytes
SHA-256: 28950b090ce131c78502ed851a9fcaffffcfb1a2559026b364bec4aeb4002572
font_01_sfnt_off0000d457.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD457 20920 bytes
SHA-256: 16b60f6457995dc3d7a7ea0d8bee086b3a1bda9a078593d7f65b5ca7ca2fc0ef