Malicious PDF — malware analysis report

Static analysis result for SHA-256 53d3d98ead95a7ec…

MALICIOUS

PDF

69.2 KB Created: 2021-09-28 14:23:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 885310ed269b992188e45b4f0b39fd7f SHA-1: 3470909059997a2db51f99e9ab110355e3b54b45 SHA-256: 53d3d98ead95a7ec4ecdce110e2fbe76b9d7a0a066a0debda2ab7aeba960949d
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as 'Pdf.Phishing.Trojan' and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The embedded URLs, while numerous, do not appear to directly execute malicious code within the PDF itself, but rather serve as lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://foundationkuzmanov.com/files/palazudogusiza.pdf In PDF document text
    • https://dalilak1.com/userfiles/file/dovexodewodedomo.pdfIn PDF document text
    • https://www.babetravelling.com/ckfinder/userfiles2/files/87289548968.pdfIn PDF document text
    • http://www.rafaellucenaehijos.com/ckfinder/userfiles/files/xuwusiwilomezi.pdfIn PDF document text
    • http://finproekt-msk.ru/userfiles/file/67281621430.pdfIn PDF document text
    • http://aybar-gallery.com/userfiles/files/xoxozunewe.pdfIn PDF document text
    • http://hanabi-la.com/uploads/files/12416839863.pdfIn PDF document text
    • http://studiofelician.com/userfiles/files/xefomejelixawixebexavux.pdfIn PDF document text
    • https://borgopitti.it/userfiles/file/tufevusaxoteririxuwame.pdfIn PDF document text
    • http://amidoux-peintures.com/ckfinder/userfiles/files/17452976517.pdfIn PDF document text
    • http://come2menorca.com/images/file/rerifoposajub.pdfIn PDF document text
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/0fcf3a65ce6b0f4ad415b589b0de9116/punulokerevokizalerelim.pdfIn PDF document text
    • https://aimtronu.org/userfiles/file/pegagugodapizazufofu.pdfIn PDF document text
    • http://fuzoku-kyujin.jp/ckfinder/userfiles/files/567831515.pdfIn PDF document text
    • https://durimawar.com/contents/files/didunog.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/161419371c7a84---nunira.pdfIn PDF document text
    • http://jiji.pgo.tw/pic/uploads/files/74376223311.pdfIn PDF document text
    • http://aodaiminhhanh.com/app/webroot/uploads/files/jusuzufaxixuxedonekexi.pdfIn PDF document text
    • http://kamennykoberec.eu/editor_uploads/system/files/dipel.pdfIn PDF document text
    • https://hotelharmika.com/assets/userfiles/files/28388423899.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16141e5a426d82---dutuvuv.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/b9c4137c3c27662e4e154d8d0ce26c77/17338055200.pdfIn PDF document text
    • http://vipnovini.bg/root/f/uploads/files/18106903641.pdfIn PDF document text
    • http://tverzhilservis.ru/foktver.ru/ckfinder/userfiles/files/14403372536.pdfIn PDF document text
    • http://thepokewave.com/uploads/files/74884630601.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=what+is+the+best+offline+map+app+for+androidPDF 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_off0000b0a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0A8 15156 bytes
SHA-256: f611cb0febeedb0f7d36c5d028310d365d75c56deac257e2af5172a1d17b7d79
font_01_sfnt_off0000d618.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD618 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ee2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE2F 10896 bytes
SHA-256: c80fe90a6d076e2676daa98631810f310b401283219de0afe1548b56febf3768