Malicious PDF — malware analysis report

Static analysis result for SHA-256 2731423e6a963503…

MALICIOUS

PDF

80.9 KB Created: 2021-09-19 12:20:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 558ec3d4295a22c7dae39e9ce95643c6 SHA-1: 5f26c1d3eeebcb3bb03ebe012f0272d9296708fe SHA-256: 2731423e6a9635035b1a3ff0463ed07472b94ac7dd6aaa560b5b42702dc7d317
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple compromised WordPress sites and disposable hosting domains, likely for phishing or malware distribution. The presence of external URIs and link farm heuristics strongly suggests an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://crewmak.ru/uplcv?utm_term=the+arc+welder+app+chrome PDF link annotation
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/c7e64d00b21c04eb8b2a5811c9faf783/zolojufuz.pdfIn PDF document text
    • https://waxparadise.pl/userfiles/file/31813063329.pdfIn PDF document text
    • http://studioaba.net/userfiles/files/dikifov.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/16139c716895df---femedagojudub.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161308f93a59fd---37127281867.pdfIn PDF document text
    • http://kocavietnam.com/upload/files/zogineg.pdfIn PDF document text
    • http://scsychem.com/upload/files/65153822218.pdfIn PDF document text
    • https://ovistar-dz.com/ckfinder/userfiles/files/lebufuliwuvulotixafom.pdfIn PDF document text
    • https://pearproperties.in/userfiles/file/jozalaximir.pdfIn PDF document text
    • http://agmapure.com/upload/files/65157084119.pdfIn PDF document text
    • https://mancomunidadvaldizarbe.com/userfiles/files/lateruluferugi.pdfIn PDF document text
    • http://crisismobile.com/ckfinder/userfiles/files/45886584545.pdfIn PDF document text
    • http://softtox.pl/new/userfiles/file/fopinakafegeduxe.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16136d601dc540---xojegesalu.pdfIn PDF document text
    • http://yugang360.com/upload_fck/file/2021-9-4/20210904150400443220.pdfIn PDF document text
    • https://resicolor.com/upload/files/13566522421.pdfIn PDF document text
    • http://candientushinko.com/images/file/69583624167.pdfIn PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16140751c7e9bf---gujuboparanuxan.pdfIn PDF document text
    • https://berbagiangka.com/contents/files/ridotijow.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/36312ec178522247731d100488008563/poliroweb.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/f4vubibnn2k427e0mh0leecvr6/xoxod.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_off0000da25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA25 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f23c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF23C 10368 bytes
SHA-256: 67c0b7f3ac9b7c9d1b0e0c5880606da2e641487faa0acceb912fd9e396156806
font_02_sfnt_off000109af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109AF 17396 bytes
SHA-256: 94af0bad676cbe2579b097b708078f360a178dad6470c937e902c59e256a0f83