Malicious PDF — malware analysis report

Static analysis result for SHA-256 7d21d717f314d284…

MALICIOUS

PDF

82.4 KB Created: 2021-10-08 10:04:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-03
MD5: 7b30f387f73c55ecf63ca79c8c020f7c SHA-1: a587144bc6c8ffb1b077b7b50cbde78739a60bf1 SHA-256: 7d21d717f314d28430f4bf2fd8420a1431f31126bf4c6c6eb51fefc1c5faddd8
164 Risk Score

Malware Insights

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

This PDF file was identified as malicious by a machine learning classifier and ClamAV. It functions as a link farm, containing numerous URLs pointing to various domains, some of which are hosted on compromised WordPress installations. The presence of multiple external URIs and the 'link farm' heuristic strongly suggest a phishing or redirection attempt, likely to deliver a secondary payload or lead users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 7

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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 http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145705e46dd0---vufakixotosorademakivapex.pdf In PDF document text
    • https://newsru.md/upload/userfiles/files/28870800858.pdfIn PDF document text
    • http://djarkitek.com/temp/vinney/HTML/userfiles/file/pewawapinimekajegomak.pdfIn PDF document text
    • https://bokaichenyu.com/upload/files/10734807791.pdfIn PDF document text
    • https://tessuno.com/upload/files/6146d452bc0a0.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/a9ddd875e57e0c99c5874e4367450748/29005902356.pdfIn PDF document text
    • http://gpszone.hu/upload/userfiles/file/60030341315.pdfIn PDF document text
    • https://melz-feu.ru/upload/16930304541.pdfIn PDF document text
    • https://vanvoorst.info/uploaded/file/1584661573.pdfIn PDF document text
    • https://deycaterers.com/ckfinder/userfiles/files/notumubulakudubogokuriwaw.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16141d44ce3381---zofoviximibudalurogim.pdfIn PDF document text
    • http://sake-tori.com/images/library/File/jilumidajodojufuludotib.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/220c3cbc6c82ff58d0ca76e95da76100/derenirukox.pdfIn PDF document text
    • http://cnmrobotics.com/files/files/pisefaf.pdfIn PDF document text
    • http://yaan121.com/uploads/files/202109280248048835.pdfIn PDF document text
    • http://ckm-machinery.com/userfiles/files/22281326776.pdfIn PDF document text
    • https://butyfarm.mm520.net/userfiles/files/35320962964.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=pc+question+answerPDF 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://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_off0000dd42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD42 18388 bytes
SHA-256: 80eb890ce5eb8992fcb2fcecb60ef11297b38801c8602a2b999f7f02d5b33a9d
font_01_sfnt_off00010cdd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CDD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000124f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124F4 10508 bytes
SHA-256: 5d7a99a2a9950d7096755fca07c521d5d565073512ef98abdd8827768d550096