Malicious PDF — malware analysis report

Static analysis result for SHA-256 99ba370eebaf0998…

MALICIOUS

PDF

72.4 KB Created: 2021-09-26 15:58:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: d459dc50c0adfbca930ee93d4190c661 SHA-1: f527419258497a4b35d8a97c2fcab9fdd7441951 SHA-256: 99ba370eebaf09989558b270b049ca5a9a4e7be840be3225feb2a387c46f975f
164 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript, a common technique for executing malicious actions within documents. The heuristic firings indicate that this JavaScript is likely used to redirect users to external URLs, many of which are hosted on compromised WordPress sites or disposable domains, suggesting a phishing or malware distribution scheme. ClamAV detection further confirms its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • 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.
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://nomylo.ru/uplcv?utm_term=pinebook+pro+android PDF link annotation
    • https://sooryasales.com/uploads/file/gowobemaregogarolerisiwoj.pdfIn PDF document text
    • https://canoe.ro/Extras/ckfinder/userfiles/files/toratigixipujoxim.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137a44faf6ea---mekivuwer.pdfIn PDF document text
    • http://zhongguohuachun.com/d/files/87418630144.pdfIn PDF document text
    • http://suachuamaydemtien.biz/userfiles/file/51361347670.pdfIn PDF document text
    • https://taechoclub.com/FileData/ckfinder/files/20210925_962728EF221E7D22.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614703f37c40d---13497358673.pdfIn PDF document text
    • https://dmitrovka-zn.ru/admin/ckfinder/userfiles/files/fejij.pdfIn PDF document text
    • http://nage-z.com/ckfinder/userfiles/files/29485976787.pdfIn PDF document text
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614308648434d---xogexuze.pdfIn PDF document text
    • https://408of53crownstreet.com/assets/media/files/15356606798.pdfIn PDF document text
    • https://chung-pei.com/userfiles/file/tizotepalokivirafebimozal.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/192bb7b9249c9d02fc3cacb959443084/bojovofuxe.pdfIn PDF document text
    • https://xn--80aaijzh9b.xn--90ae/documents/file/vekud.pdfIn PDF document text
    • http://qiuyutv.com/userfiles/files/20210912025343.pdfIn PDF document text
    • http://korea-seals.com/ckfinder/userfiles/files/54005209320.pdfIn PDF document text
    • http://wskinbody.com/data/boardData/files/38894516748.pdfIn PDF document text
    • http://aisne.proximeo.com/ckfinder/userfiles/files/berik.pdfIn PDF document text
    • http://netflor.pl/upload/File/livotofebatasej.pdfIn PDF document text
    • http://fundacjaproartis.pl/javascript/ckfinder/userfiles/files/67343023092.pdfIn PDF document text
    • https://podimercrm.com/img/files/bejarofob.pdfIn PDF document text
    • http://delve-cr.com/uploads/jilibopidigosomobedafasav.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_off0000b404.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB404 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cc1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC1B 10304 bytes
SHA-256: f4920409a0df79faaf82a1fb5ad83f8f6d7bd048ec745630a2582928c66f5838
font_02_sfnt_off0000e322.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE322 18504 bytes
SHA-256: 7e9e9982278812d3b14d74c85f95e36ced35d166ac7ccb713b8f65bae31b7f23