Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f27ae94267e2bac…

MALICIOUS

PDF

89.0 KB Created: 2021-06-20 14:48:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 1cb778d6ba661f29ad2932ef27f159c2 SHA-1: f1b203e84e20ed7d409a97eb4e829580c7a5afc3 SHA-256: 3f27ae94267e2bac2cb71d2a47c37b79b4e8b24a7268e3ba7671028b04c66de8
156 Risk Score

Malware Insights

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

The PDF file contains numerous links to external websites, many of which are hosted on compromised WordPress installations, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent, with the document body containing garbled text but referencing a '4 pics 1 word' game, a common social engineering pretext. No scripts were extracted, but the overall structure and URL patterns are consistent with phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://inwebjor.ru/uplcv?utm_term=4+pics+1+word+8+letters+daily+challenge PDF link annotation
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609680a7d95d5---muzozitixafimepagugur.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/16084cb5d8a893---bokivolotoduwemaxepuj.pdfIn PDF document text
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/1a94b8e924672f8e0416aedac92464de/17136953073.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160baadfce7ce3---52311884554.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16082167242495---lugolekanesaladojaja.pdfIn PDF document text
    • http://amako-ra.com/wp-content/plugins/super-forms/uploads/php/files/eb68eb0c739911cc72bbe882d51ab7b9/jelowasosuzojudomamoxenog.pdfIn PDF document text
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c4f99101ba---rozokebevib.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0ca91a2517---zewefuwinasamef.pdfIn PDF document text
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/c43qvnatjudh2jvc4shk549i55/54529732897.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/538fc64ae39e11919746190383bc1649/futazupupegivatemasepit.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609f6a53df136---15533489346.pdfIn PDF document text
    • https://thetitangroup.ca/wp-content/plugins/super-forms/uploads/php/files/b7864c92d7163cb27d0df8fedd3cc9c4/35623300627.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afedee66f01---jinil.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/e9857edd049dc3922d8538cdbfc9bb8d/97943574630.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c833ae0ca5---kofidifujufutewowafopuwa.pdfIn PDF document text
    • http://donaldnathanlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/warukizekipubed.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011f01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F01 5768 bytes
SHA-256: f2b4bb27df28ea318a61af455cf42f678fdf60c645607ebf9f8d2bf3dea41884
font_01_sfnt_off000132bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132BF 10732 bytes
SHA-256: d4da25688ec5180a2a2981266c56d7376a435920404a70bb71d7d911a8e51f2d