Malicious PDF — malware analysis report

Static analysis result for SHA-256 135d5893c18aa1f9…

MALICIOUS

PDF

158.2 KB Created: 2021-06-24 19:03:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: f29a2ed5225b74569981a209c00f8e45 SHA-1: e158747c23ac1637bf8732b25e6160bb73dc7743 SHA-256: 135d5893c18aa1f94ba3ff0560638f92126d001702766e2515bc8cd20bf36ae9
156 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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://arket.io/wp-content/plugins/super-forms/uploads/php/files/t751hmh3gm7u7h9snjr0gmbveg/55299924809.pdf In PDF document text
    • http://laweasy.kr/userfiles/file/76163793264.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/96tapbn4vc4timaat98uaqhmtv/75946717275.pdfIn PDF document text
    • http://lafenicealcamo.it/userfiles/files/juxinotusuwigi.pdfIn PDF document text
    • https://altbuket.ru/files/56029955921.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/0caf7a1e6170a6a809c959d56375628b/94286884846.pdfIn PDF document text
    • http://brenno-tojestto.pl/userfiles/file/jevuxokovenewonam.pdfIn PDF document text
    • http://altaprecision.com/userfiles/file/17878535733.pdfIn PDF document text
    • https://paklya.su/design/img/upload/file/bowibijofab.pdfIn PDF document text
    • https://rsun.pro/admin/ckfinder/userfiles/files/40686790044.pdfIn PDF document text
    • http://gentlemensquartersbarbershop.com/wp-content/plugins/super-forms/uploads/php/files/4c7f6b3592a674b84c995e8b0ccaf4e1/bovizuvon.pdfIn PDF document text
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c3c7529c34---69478629067.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/lq5ha3259ovs31240l036uq5nv/xikaderanofubewuwebusame.pdfIn PDF document text
    • http://brandiassociati.it/userfiles/file/xovinekegaladow.pdfIn PDF document text
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1607994a069567---46829221886.pdfIn PDF document text
    • http://fxmeat.com/upload/file/769e0206e8bad5705b01c2da45c71be7.pdfIn PDF document text
    • http://bannermaul.com/userData/board/file/9836609116.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/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=lei+4771+65+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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00020de8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x20DE8 4448 bytes
SHA-256: 96b7a20a864fa3e66991799e833482ae894b720f9788a92455d3bf025bfa74a8
font_01_sfnt_off00021d20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x21D20 13524 bytes
SHA-256: a6b70fc78ed5f2e166b00a692c86d371b93f676175e497dcab03d4f2428f2223
font_02_sfnt_off0002465a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2465A 16204 bytes
SHA-256: e93acd332f5893643511f4cefd38969ad5c744ad1b08842a788b6be7d277dd15
font_03_sfnt_off00025b88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x25B88 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333