Malicious PDF — malware analysis report

Static analysis result for SHA-256 23d3eadb26e3c84b…

MALICIOUS

PDF

94.1 KB Created: 2021-06-24 15:19:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 764ea6e82202e9b22f7b24e35d300c40 SHA-1: 0ef2ffc0ab110dcdc35b28e71aa617dab3aac5d9 SHA-256: 23d3eadb26e3c84b1bccdab4d22270a3b0753da636bca49fa1df81068a8ef653
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites hosted on compromised CMS platforms, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a phishing or malware distribution attempt, likely leveraging embedded JavaScript for redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/df08314d9ed8609d3e84a7dcb97c537a/8831462551.pdf In PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/2431b6b2369c5bde8613b4bce99aca7d/gokukatoxafenupowi.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/uliiqaumj9t10pb07ggouinep5/23542722199.pdfIn PDF document text
    • https://atamergranit.com/userfiles/file/76352508191.pdfIn PDF document text
    • https://www.lightingdynamics.com/wp-content/plugins/super-forms/uploads/php/files/8d90ee803e84fde0395bd66e0c892ff0/8943499109.pdfIn PDF document text
    • https://fertilizergranulatorprice.com/d/files/32748574385.pdfIn PDF document text
    • https://premiumvipbusiness.com/wp-content/plugins/super-forms/uploads/php/files/4564d14e17340e2c9afe28b28ebceb8f/motiwuximu.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/grj67c2unu47pelhjh496q18v4/48740563093.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16079f43650fb1---sululunogobovimozog.pdfIn PDF document text
    • http://www.niziointerior.pl/upload/file/zefaweworefadajagizuvazow.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16074299678c80---24041425528.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/6e10a6b499b18f281effdca8f33c8542/pinizekipupe.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1606e7072c23b7---fetolariwuronowa.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608153e2bd0dd---soraloxubigomomolatavu.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/il1t42u6guvlm6ijojn7ehgoj5/kukunopozimototil.pdfIn PDF document text
    • http://www.alex-vasilkov.ru/images/wisdom/file/23335148657.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=official+sat+book+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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012871.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12871 4848 bytes
SHA-256: f8426fc818ab1a273981d2e46c7a654a21f79a878cdd29cda1e2cdea2efdb4d1
font_01_sfnt_off000138ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x138EA 10660 bytes
SHA-256: 1ccab91a614e9c898ef890a5bc6a80cf084b53e3099c5273596880033fa464dd
font_02_sfnt_off00015d6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15D6D 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3