Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4cd86eb6cbfcb89…

MALICIOUS

PDF

74.5 KB Created: 2021-06-25 02:29:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 600572305d1647205e655995a7189ccd SHA-1: 0dd851df0ff420841a92c67c00df2004d479abe9 SHA-256: f4cd86eb6cbfcb898bc74047180bc57ade52e70acda9e83bc4ca1c27e6f19426
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains a link farm pointing to compromised WordPress uploads and disposable hosting, suggesting an attempt to redirect users to malicious content. The embedded URLs and the nature of the heuristics indicate a phishing or redirection attack, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/cb834e54a38080a1268c6b776e28704e/14364658616.pdf In PDF document text
    • http://xn--9d0b102a6wc3y4a.com/sa_upload/userfiles/file/20210520054205.pdfIn PDF document text
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/040c581d16746063fd679f89c16542ff/jedaxex.pdfIn PDF document text
    • http://au-coeur-du-temps.com/userfiles/file/rofelatat.pdfIn PDF document text
    • http://abbuffalowings.com/uploads/files/modimemumoxuxesaxinuvad.pdfIn PDF document text
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/ub1o0g4986dpdc8dr4sm6ji5q9/32314781966.pdfIn PDF document text
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6e67b64044---49640242135.pdfIn PDF document text
    • http://bajcsidavidfoto.com/_user/file/wemidefomaki.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/071358339804.pdfIn PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1508e6be7---85414803162.pdfIn PDF document text
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077d8d4b2c3a---17048843414.pdfIn PDF document text
    • https://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/6c69a563bf7f62f5f496152f5aa82343/84211023642.pdfIn PDF document text
    • http://ofipapel.org//ckfinder/userfiles/files/lodedolobokolidazafazazak.pdfIn PDF document text
    • http://hongdacable.com/d/files/66382241620.pdfIn PDF document text
    • https://maspacientes.es/wp-content/plugins/super-forms/uploads/php/files/cd4thk7kqp2p0ri1lnjt073upv/zagugedusibekomubivip.pdfIn PDF document text
    • https://kodcomputers.ro/2664/uploads/15598973642.pdfIn PDF document text
    • http://maility.pl/_ADRESuserfiles/file/45777291547.pdfIn PDF document text
    • https://bd-sokolovska.eu/userfiles/file/68269041457.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/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=physics+general+knowledge+quiz+pdfPDF 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_off0000e38c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE38C 5852 bytes
SHA-256: f8e00dd94e9d4f7c90d78c2d93f87c5ba0bfbc9a8b27e83a029f1fcdb0059498
font_01_sfnt_off0000f793.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF793 11108 bytes
SHA-256: 99f30a93235b5e3d11f491e0d01bd7215ae9bad2ca8ea80116f129f168836f46