Malicious PDF — malware analysis report

Static analysis result for SHA-256 28867c37b2e306ab…

MALICIOUS

PDF

77.1 KB Created: 2021-06-19 13:18:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 7f02168df97ea043b3d493a27e576979 SHA-1: de51a5d41a54d69f19a29a070881215b1e530174 SHA-256: 28867c37b2e306ab3bde7b39366756987a45a8741d304858ad403e138280d22d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

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 and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/0icgas4at5tjb9nqmpifsd7f61/tarujoxuxe.pdf In PDF document text
    • http://alnoorcity.com/userfiles/file/pixababirugesiwitaramak.pdfIn PDF document text
    • https://daleel.global/wp-content/plugins/super-forms/uploads/php/files/2c2o7otns3k3mpngqimuot66er/46869759510.pdfIn PDF document text
    • https://doellefjelde-mussemarked.dk/images/newsmail/file/17132912158.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f18794582e---salufulopoji.pdfIn PDF document text
    • http://pvsystreports.com/wp-content/plugins/super-forms/uploads/php/files/di9j9tojjsa0oemq3e0jvi6jn4/95450371461.pdfIn PDF document text
    • https://gfow.om/wp-content/plugins/super-forms/uploads/php/files/k79etlcd9jequi9o28eb0t41l8/37151714560.pdfIn PDF document text
    • https://alakharia.com/public_html/userfiles/file/375383017.pdfIn PDF document text
    • http://greatnice.club/updatefiles/file/20778112576.pdfIn PDF document text
    • https://nikosdimos.gr/userfiles/file/rajezo.pdfIn PDF document text
    • http://drironcat.com/images/file/27129814358.pdfIn PDF document text
    • https://www.vbclighting.com/wp-content/plugins/super-forms/uploads/php/files/62174c1e188debd4433de6a3993d978f/xetizegavurus.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/1e1ca6b0db75294f9d99bff52256ead1/nudegegenof.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608303b0bfdc6---46663633770.pdfIn PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/1607f5b3dea9fe---43874317197.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/160c77c5acc8da---tudukezijofoguj.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=dhoom+3+movie+free+downloadPDF 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f162.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF162 5284 bytes
SHA-256: 681355c47b0e885338dcdd1a1a024cec89d387c9415609ea86657639caf36e4c
font_01_sfnt_off00010353.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10353 10648 bytes
SHA-256: cd72b4d06dca4f58c7e4aa1f2688d08f50fea9cfb257f326a24574aabb1daa70