Malicious PDF — malware analysis report

Static analysis result for SHA-256 c478e5a4dfc6faaa…

MALICIOUS

PDF

76.0 KB Created: 2021-09-17 05:07:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f7ef6a3c581f6c045be1b0d7b91e6a12 SHA-1: c7142e974dcf8f35a1deace9126d1d6a79758610 SHA-256: c478e5a4dfc6faaa613272ffc518da5839ed74813cc2187526ec6d9991eb2658
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged by ClamAV as a phishing trojan and by an ML classifier with high confidence. It contains numerous links to external websites, many hosted on compromised CMS platforms or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of PDF_RANDOM_URL_LINK and PDF_SEO_DISPOSABLE_LINK_FARM heuristics indicates a pattern of distributing malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://nguoixunghekiev.vn/userfiles/file/zadetep.pdf In PDF document text
    • http://www.gdchgs.com/admin/img/files/51279325469.pdfIn PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/68d668cc2ccc3bb0d35678247b9be3d2/veranuwotisipogadajodoju.pdfIn PDF document text
    • http://devveb.net/userfiles/file/fanilozilolesadojufifelem.pdfIn PDF document text
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/12736225735.pdfIn PDF document text
    • http://hepiran.com/cache/fck_files/file/62242542759.pdfIn PDF document text
    • http://business-baltic.com/myfiles/dok/2839235584.pdfIn PDF document text
    • http://koreaseowon.com/ckupload/files/11622535340.pdfIn PDF document text
    • http://samnakthodrahassob.com/userfiles/file/gabowutafudewogikiw.pdfIn PDF document text
    • http://ambulatorioveterinariopisillibertozzi.eu/userfiles/files/24912156132.pdfIn PDF document text
    • https://glycocalyx.nl/userfiles/image/file/vazowexidejesupemizufiw.pdfIn PDF document text
    • https://dongciao.com/uploads/files/202109111418482628.pdfIn PDF document text
    • http://songhakbbq.com/uploads/files/73246825162.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/2104f38e7c2c56b766b3f529934a6d6d/fuzuwataz.pdfIn PDF document text
    • https://toocapen.com/files/39273933568.pdfIn PDF document text
    • https://mamotato.ro/userfiles/file/77822364333.pdfIn PDF document text
    • http://anais.terminarz.online/kosmetyczka/krakow/files/sivakigamotafasetaso.pdfIn PDF document text
    • http://www.injamal.es/nueva/ckfinder/userfiles/files/febizalokum.pdfIn PDF document text
    • http://tcgardening.com/userfiles/file/2021090812423773499.pdfIn PDF document text
    • https://kccegis.com/upfiles/content/file/20210913150945.pdfIn PDF document text
    • http://iwilldoit.ru/uploads/files/files/mipivudotupo.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1613b8c34267ba---dubulujijesulasomovada.pdfIn PDF document text
    • http://bright-mineral.com/uploadfile/file/2021090802281981.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=best+coop+game+pc+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_off0000c566.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC566 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dd78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD78 17012 bytes
SHA-256: 8bcec55df15610c42bee50e0a68e38aa7e7f9a189f90809750cb4ddae74fdc74
font_02_sfnt_off000109a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109A3 10720 bytes
SHA-256: 01275e09f08e9dcf0809c29b00d265cb49d778378381dff291b928fab13745c3