Malicious PDF — malware analysis report

Static analysis result for SHA-256 955539cab27cc691…

MALICIOUS

PDF

92.9 KB Created: 2021-09-24 00:49:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b2a574e20d1ecacbc039838d7ed41b99 SHA-1: 1c1b63d14007a5b005f1063839580d01c01e6bea SHA-256: 955539cab27cc691262bf9ef4b42e64ee469a2e614c5079cadef4847e938c64f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that form a link farm, many pointing to disposable hosting or compromised CMS uploads, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious sites, likely for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9897

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://pistant.ru/uplcv?utm_term=download+wifi+hacker+for+android PDF link annotation
    • https://kisikana.hr/UserFiles/files/48709827900.pdfIn PDF document text
    • http://kingsap.com/file_media/file_image/file/guzogirim.pdfIn PDF document text
    • https://divinenine.net/userfiles/file/23182896414.pdfIn PDF document text
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16135a7ca6d219---98986673074.pdfIn PDF document text
    • http://gnatowski.pl/attachments/file/garefigivabujotaxel.pdfIn PDF document text
    • http://dietmoiquangle.com/webroot/img/files/vizufijovewolixotu.pdfIn PDF document text
    • https://grupa-energia.pl/attachments/file/gavafenebudunafa.pdfIn PDF document text
    • http://contua.org/userfiles/file/19016424852.pdfIn PDF document text
    • http://naszemotyle.natura2000.pl/imgturysta/files/23711612809.pdfIn PDF document text
    • http://mudrkanuch.sk/editor_uploads/system/files/66167106838.pdfIn PDF document text
    • http://indigobaby.eu/upload/files/48468364996.pdfIn PDF document text
    • https://mimpishio2bet.net/contents/files/foriponu.pdfIn PDF document text
    • http://edallyshop.com/upload/files/70164957532.pdfIn PDF document text
    • http://shahgrp.com/uploads/pumumavobiwubevipusasufo.pdfIn PDF document text
    • http://allamericannursing.com/userfiles/file/320176487.pdfIn PDF document text
    • https://elnativocoffee.com/silver/upload/files/92242316046.pdfIn PDF document text
    • http://dakdekkersindex.nl/images/uploads/83880188047.pdfIn PDF document text
    • http://xn----dtbsgbucafmmaf.xn--p1ai/servimages/editor/files/7185077638.pdfIn PDF document text
    • http://ingore.cn/upload/files/pafafon.pdfIn PDF document text
    • http://g-shocktou.com/user_file/file/biguwe.pdfIn PDF document text
    • http://svazekobciorlice.cz/userfiles/file/rupisobepo.pdfIn PDF document text
    • https://irepairplus.nl/app/webroot/files/userfiles/files/zilomuxulufafo.pdfIn PDF document text
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/b0646485d09731189272ae855707dd67/24318072601.pdfIn PDF document text
    • http://wawa757.com/uploads/files/doxenabujot.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614c9c8e30048---47471722310.pdfIn PDF document text
    • https://orrizon.ru/images/file/gidezokawesowawa.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_off0001045e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1045E 10488 bytes
SHA-256: 5cb6e7744d8d83e4474ce41ac5c2ded701a10b09604bc5e5b4d6d4fc49dbfbed
font_01_sfnt_off00011c1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C1E 18808 bytes
SHA-256: 44cba31c5770051f94ad1d437fefe885f09da6ae9ba5adb95c4610bd6b8b6b88
font_02_sfnt_off00014d50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14D50 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1