Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4ef8c0e3401e52b…

MALICIOUS

PDF

76.6 KB Created: 2021-09-21 05:03:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 2a543220d5d8127499f3c21e3bb17ff0 SHA-1: d143c20cabac0087c2a1cb72d490c01ac178a85f SHA-256: c4ef8c0e3401e52bb0d2396fe69bdb14dd8bce2c031007bc674cd4943c2c1f6b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. While no scripts were explicitly extracted, the PDF structure and embedded URLs indicate a likely intent to redirect users for phishing or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://poltinka.ru/userfiles/file/febezuxanisogu.pdf In PDF document text
    • https://vico-domrep.com/ckfinder/userfiles/files/pasoritokilanutakasuno.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130a70c6eb5c---gonaxeronenojixuluvif.pdfIn PDF document text
    • http://maximaviajes.com/FCKfiles/file/45427817504.pdfIn PDF document text
    • http://fedime.org/imagenes/degavadubamaravenare.pdfIn PDF document text
    • https://www.oasipizza.it/wp-content/plugins/formcraft/file-upload/server/content/files/161450077b155a---xojifofabeneloropekifaba.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/16149023d7c398---91983955548.pdfIn PDF document text
    • http://bienchidan.org/uploads/files/59685223539.pdfIn PDF document text
    • https://tecnibat.net/uploads/archivos/logevaratuwamimunagi.pdfIn PDF document text
    • https://408of53crownstreet.com/assets/media/files/lodejitogibo.pdfIn PDF document text
    • https://verner.lt/images/files/podiwaxigalubogowazokek.pdfIn PDF document text
    • http://asja.ua/userfiles/file/55791882347.pdfIn PDF document text
    • http://domingo.hu/ckfinder/userfiles/files/bepenoretikeboroxikow.pdfIn PDF document text
    • http://rockhouseschool.com/rockhouse/uploads/files/22849677509.pdfIn PDF document text
    • https://webmedcentralplus.com/userfiles/file/88389820690.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/161328299a8eb5---viwafikatuvuduneb.pdfIn PDF document text
    • http://haraj-alqunfudhah.com/userfiles/file/rudewopesetudog.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/1dcaf1b8ef90f479f7a08d370f44f680/28858403845.pdfIn PDF document text
    • http://fortwashington.abwingsmd.com/uploads/files/88312257980.pdfIn PDF document text
    • http://toyotarent.hk/FileData/ckfinder/files/20210918_006EE3AEB6D1E5BF.pdfIn PDF document text
    • http://maiodi.com/userfiles/files/82812240741.pdfIn PDF document text
    • http://harckocsik.hu/userfiles/file/77025605615.pdfIn PDF document text
    • http://ingmontagna.com/userfiles/files/lalorivawukedodiwujef.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=oet+reading+samples+for+nurses+pdf+2021PDF 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_off0000c406.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC406 17644 bytes
SHA-256: a1451d715d9fd68a4cb4efc0c6fbe08b230d32dc5fd5eb3db2b9b941dbc8698e
font_01_sfnt_off0000f22e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF22E 11260 bytes
SHA-256: c137f536df0c54045829ce1f983b53260c54490e5e821af4b42a4fece6bd1d9a
font_02_sfnt_off00010c6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C6F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.