Malicious PDF — malware analysis report

Static analysis result for SHA-256 87f22a4f70ad0ce1…

MALICIOUS

PDF

69.9 KB Created: 2021-09-02 04:15:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 30f6f6a2b799cfe91fe45471ebfa7f7f SHA-1: b5199c964a472cedf2d864be035568745962d7f3 SHA-256: 87f22a4f70ad0ce1eb99c28cb7e5d6eab8c05e2606a98403e5bf7cd634b10e15
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to compromised websites or disposable hosting, suggesting a phishing or malware distribution scheme. The document body was heavily obfuscated and unreadable, providing no direct content clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/83jm5i54ajnd88n8hn8sv70uf6/66499936402.pdf In PDF document text
    • http://fewo-spreewald-schoetzigk.de/brandenburgtag/img/editor/file/71381763156.pdfIn PDF document text
    • http://turinhotelcompany.com/userfiles/files/jevunidodesaso.pdfIn PDF document text
    • http://keralabiblesociety.com/fck_uploads/file/51384993997.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/d05fc4f0086e3860cb6f624c151858c1/17575391120.pdfIn PDF document text
    • https://horizontire.com/userfiles/file/95367537507.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/oema3dkopfrjrofvu1af4jplu9/38529777561.pdfIn PDF document text
    • http://17njl.com/userfiles/files/jaxujabu.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160aa5bc581014---58877757083.pdfIn PDF document text
    • https://cakenepal.com/userfiles/file/kifutunigifokukomul.pdfIn PDF document text
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ccec69a1978---divemozazenitalufifunegal.pdfIn PDF document text
    • http://rocincorporated.com/domain.com/images/dynamic_pages/file/3663520314.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/160a63bd756c89---28428550747.pdfIn PDF document text
    • https://k2salight.com/wp-content/plugins/super-forms/uploads/php/files/9459962364984c6786ee78a3dd92b2e7/50589825843.pdfIn PDF document text
    • http://kiiga.ru/userfiles/file/gelalirujefis.pdfIn PDF document text
    • https://10glazsikeyrosa.ru/file/7137880172.pdfIn PDF document text
    • http://share-world.tw/userfiles/file/91032337359.pdfIn PDF document text
    • http://alemotta.com/resources/original/file/5334700614.pdfIn PDF document text
    • https://minlinart.com/archive/upload/files/xadudoveri.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fad1026469d---21924123720.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=pd+705+revised+forestry+code+of+the+philippinesPDF 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_off0000b2c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2C1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cad8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAD8 11040 bytes
SHA-256: 206bb145388bab677aff5d1cb3b79160504978602d84e7918099e5edb3fc3f21
font_02_sfnt_off0000e49a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE49A 14860 bytes
SHA-256: df5bf4d7a84fd186d66d2c398250d8e95ddf4a8b41a313832bc9281c335db8aa