Malicious PDF — malware analysis report

Static analysis result for SHA-256 353b4f8cae05e7c7…

MALICIOUS

PDF

70.1 KB Created: 2021-09-10 05:19:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 15c9be14944daa59da8300b565bad8a5 SHA-1: da6d3b73e1873766536a7b8279e8a63fb3bac50a SHA-256: 353b4f8cae05e7c7a79c1281f2db078c05d609f0cf84a27ea4a5231b378a374a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a large number of external links, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to lure users to potentially malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://philabc.ru/uplcv?utm_term=resident+evil+7+free+download+for+android PDF link annotation
    • https://annekienlen.fr/imagesfile/nezemovogiwef.pdfIn PDF document text
    • http://amunt.madteam.net/ckfinder/userfiles/files/juvulunonelomejixe.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1612fffe933eb1---93729188006.pdfIn PDF document text
    • http://rotarybrescello.it/userfiles/files/xuxarimafigepexidapesopu.pdfIn PDF document text
    • https://wspaperbag.com/userfiles/file/93825591570.pdfIn PDF document text
    • http://liluby.com/upload/file/jowurubelolanuwes.pdfIn PDF document text
    • http://lapempi.nl/ckfinder/userfiles/files/kipikebivorop.pdfIn PDF document text
    • http://smarttechsolutionukltd.com/uploaded_files/userfiles/files/42125567327.pdfIn PDF document text
    • http://fioredda.com/userfiles/files/tuwironofuxusutori.pdfIn PDF document text
    • http://dexgerm.com/data/file/userfiles/files/9693298927.pdfIn PDF document text
    • http://elma1.ru/!upload/files/reputexepadaregirov.pdfIn PDF document text
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/cotttg4pv0kp9or07qhq0450fi/beboriruwipozuj.pdfIn PDF document text
    • http://partnercable.com/files/73126030213.pdfIn PDF document text
    • http://www.kyousei-fukushi.or.jp/system/ckfinder/userfiles/files/pasevunepifex.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612f6c6d8c169---68010501026.pdfIn PDF document text
    • http://huntland.hu/upload/file/57096405949.pdfIn PDF document text
    • http://aan.kz/ckfinder/userfiles/files/lulibegaso.pdfIn PDF document text
    • http://copy-office.it/userfiles/file/19571019610.pdfIn PDF document text
    • https://allora-tour.by/var/upload/file/92454156564.pdfIn PDF document text
    • http://reversetheclocknow.com/ckfinder/userfiles/files/89281708643.pdfIn PDF document text
    • http://optikametuje.cz/userfiles/file/39813222597.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_off0000b138.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB138 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c94a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC94A 16016 bytes
SHA-256: 69ee9c9ca51363dae19b4c4759c7d554d5afe269922b15952674f0906fafed18
font_02_sfnt_off0000f296.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF296 10592 bytes
SHA-256: 4f133650c828d649fbd880f47d9ba6d1e9f343d50ca7bf2333ddbbaebfe9670b