Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf5490cfc7b65cba…

MALICIOUS

PDF

71.8 KB Created: 2021-09-11 18:23:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 3d590b7f2454e946c09df85b3a4fc96a SHA-1: 6c90698640a275b2eb0c161182feb642d390411d SHA-256: cf5490cfc7b65cba357156e2c06fd2fd48c0007808c2594743a70a6197922eef
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous external URIs and is identified as a link farm on disposable hosting, suggesting it's used for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest it's designed to lure users to malicious websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://archism.ru/uplcv?utm_term=find+derivative+using+chain+rule PDF link annotation
    • http://scantech3d.com/files/749328270.pdfIn PDF document text
    • https://thailonghoang.vn/upload/files/zibidalosikopabas.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613825ba57254---sudarunilovilufobevujexiv.pdfIn PDF document text
    • http://erodiertechnik-wenzel.de/userfiles/file/83906791380.pdfIn PDF document text
    • https://greenbins.ca/ckfinder/userfiles/files/jumofal.pdfIn PDF document text
    • http://etoprosto.ru/ckfinder/userfiles/files/34260440209.pdfIn PDF document text
    • http://hkxhjfc.ltd/uploads/files/20210904125050.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/merezosovavaxefom.pdfIn PDF document text
    • http://benetworkingpro.com/ckfinder/userfiles/files/migiba.pdfIn PDF document text
    • http://atut-biuro.com/uploaded/file/mivuzosogomeniv.pdfIn PDF document text
    • http://tt-ural.su/admin/ckfinder/userfiles/files/70920014792.pdfIn PDF document text
    • http://dkind.net/userData/board/file/19489448458.pdfIn PDF document text
    • https://slezanie.eu/userfiles/file/59208751746.pdfIn PDF document text
    • https://pensiuneaselina.ro/userfiles/file/19550767535.pdfIn PDF document text
    • http://eot.mn/uploads/userfiles/files/72917820036.pdfIn PDF document text
    • http://chiangmai-clean.com/user_img/files/66309382145.pdfIn PDF document text
    • https://hometeamcorp.com/images/usr/90915929593.pdfIn PDF document text
    • http://archinfo.ru/uploads/file/sijinig.pdfIn PDF document text
    • https://greenfuturevietnam.com/Upload/files/favowibevolidar.pdfIn PDF document text
    • http://alpinist.store/sribati/editor/uploadfiles/nawikidisorakarezido.pdfIn PDF document text
    • http://retrievers.su/ckfinder/userfiles/files/rokitanasuval.pdfIn PDF document text
    • http://locke-3c.tw/uploads/files/202109051000316540.pdfIn PDF document text
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/b0a09381a1ba852fddd9394b3b80762b/2724075526.pdfIn PDF document text
    • http://checopharma.com/upload/files/betowizekuzipumu.pdfIn PDF document text
    • http://futimisdev.com/userfiles/file/75239184922.pdfIn PDF document text
    • http://jumpstart.mobi/ckfinder/userfiles/files/ragipetixuzupatilomam.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_off0000b915.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB915 15904 bytes
SHA-256: 6531d3d9f75e1204a0ec3604d1b93e9e82cba448a26050fd80788e99a9dd5fe0
font_01_sfnt_off0000e1a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1A7 10672 bytes
SHA-256: 2e9930aadb4c695739de6419733a0e379b7008461173d054c5b9a5e7c6ae2683
font_02_sfnt_off0000f9cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9CF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1