Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1a2bdb8a0091adc…

MALICIOUS

PDF

82.8 KB Created: 2021-09-22 12:35:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f73d5406a9115abbd0801b4a6eaba15b SHA-1: 047215b586e0ce8646d9ff39cf513ec97f9e238c SHA-256: c1a2bdb8a0091adc31fd757156f5856072b39d31010157da528e971bf15798a8
156 Risk Score

Malware Insights

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

This PDF file contains a large number of embedded URLs, many of which point to compromised WordPress installations or other disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or to serve further malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests a deliberate attempt to create a link farm for SEO manipulation or to distribute malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://inwebjor.ru/uplcv?utm_term=resident+evil+4+lite PDF link annotation
    • http://chulatutoracademy.com/chulatutor/ckfinder/userfiles/files/soritesuradoxe.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614809a7503da---86034022267.pdfIn PDF document text
    • http://puzynowska-kancelaria.com/userfiles/file/63197266472.pdfIn PDF document text
    • http://www.niceresidence.net/image/upload/File/12645996312.pdfIn PDF document text
    • http://electriccityusa.com/images/fck_uploads/file/96997532035.pdfIn PDF document text
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/32a56375c250ae7267e261798b00e4b2/74056333940.pdfIn PDF document text
    • http://rujiahk.com/uploadfiles/file/98763314654.pdfIn PDF document text
    • http://twfbs.com/ckfinder/userfiles/files/22768261365.pdfIn PDF document text
    • http://epodhajska.eu/UserFiles/File/21139119165.pdfIn PDF document text
    • http://gemculture.com/userfiles/file/39587822136.pdfIn PDF document text
    • https://binarbaidequipment.com/public_html/userfiles/file/rolotikamezomixomo.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613e5c3e7a360---zatigojegab.pdfIn PDF document text
    • http://geonatlife.es/ckfinder/userfiles/files/49425424604.pdfIn PDF document text
    • http://redskap.ru/userfiles/file/34396968423.pdfIn PDF document text
    • http://orvositudasbazis.eu/images/upload/file/84916128953.pdfIn PDF document text
    • http://strandedtattoo.info/file/xobavebitumuri.pdfIn PDF document text
    • https://soroptimist.be/oldsite/intranet/ckeditor/ckfinder/userfiles/images/files/goxumobuzavane.pdfIn PDF document text
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/161378cd373e51---43812276054.pdfIn PDF document text
    • https://themalc.org/files/file/rakikagabuwajonam.pdfIn PDF document text
    • https://dentalrud.com/userfiles/file/jaliguvuvakexakivasowame.pdfIn 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://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_off0000e364.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE364 10048 bytes
SHA-256: 7d8e1b83c171eafbf501f57a9afe52bff71f269acd82d83f307faf274a053c69
font_01_sfnt_off0000f9e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9E3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000111f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111F5 17112 bytes
SHA-256: bdda8b594c3c665ebc7bd3fa1bb7f7c568b515182e6655c2c4c2c18398cedcdf