Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e3d1bcb9d421902…

MALICIOUS

PDF

88.6 KB Created: 2021-09-17 13:10:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 50f81086a3e20c78067711952d393b77 SHA-1: e8f4d5e74975e7b02bb094fe47ef98ea45479c51 SHA-256: 8e3d1bcb9d421902ee3c3fdf27eec6a448b57f2464f17ef8972aad2c4488a93c
156 Risk Score

Malware Insights

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

The sample was detected by ClamAV as Pdf.Phishing.Trojan and ML classifiers also flagged it as malicious. Numerous heuristics indicate the PDF is a link farm, with many URLs pointing to compromised WordPress uploads or disposable hosting, suggesting a phishing or malware distribution scheme. The presence of embedded URLs and the overall structure strongly suggest this PDF is intended to redirect users to malicious websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://crysiq.ru/uplcv?utm_term=nama+os+android+dari+awal+sampai+akhir PDF link annotation
    • http://webbuilders.com/files/file/lojipobozuzumuwiwujifuj.pdfIn PDF document text
    • https://a-pointpro.com/cms/ckfinder/userfiles/files/24833549904.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/29c5cea0d1e07b36cf3c20e21d0ceff7/75953128628.pdfIn PDF document text
    • http://www.reeder.ee/files/filemanager/51470372927.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/c76bcff6876b9996117ef8daa5d9201f/93508970971.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e5f5b70e2e---rimagufebebifozis.pdfIn PDF document text
    • https://minhvuongthuphap.com/upload/ck/files/78008971885.pdfIn PDF document text
    • http://pinxedien.net/upload/files/61529342943.pdfIn PDF document text
    • http://sangjeom.com/userfiles/file///72432745070.pdfIn PDF document text
    • https://wodepcb.cn/uploadfiles/files/25250706210.pdfIn PDF document text
    • http://sipsak.nl/userfiles/file/piramasolisod.pdfIn PDF document text
    • http://susasoft.com/upload/userfiles/files/44459427091.pdfIn PDF document text
    • http://marienoellebermond.com/img/uploaded/file/90651840312.pdfIn PDF document text
    • https://bulgariapools.com/contents/files/53877508524.pdfIn PDF document text
    • http://gianenricofabro.com/userfiles/files/betareretulosobigivuvupi.pdfIn PDF document text
    • http://czpohledavky.cz/userfiles/files/wazuxonawakevitunobubag.pdfIn PDF document text
    • https://newsale.linyn.mobi/upload/ckeditor/pages/files/91115920848.pdfIn PDF document text
    • https://takipcisec.com/calisma2/files/uploads/70674062761.pdfIn PDF document text
    • https://rubyyadav.com/nbloom/fckuploads/file/88576471937.pdfIn PDF document text
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/d282258e3ab16327359cc324aa1f1773/likofojanaxig.pdfIn PDF document text
    • http://astprom.ru/sites/default/files/file/gotorerikisakeruvib.pdfIn PDF document text
    • http://akekaluck.com/ckfinder/userfiles/files/remojasevarawepukom.pdfIn PDF document text
    • http://improntediteatro.it/userfiles/files/78553924131.pdfIn PDF document text
    • http://neodev.space/wp-content/plugins/formcraft/file-upload/server/content/files/16132dea3e41bb---wasuvonoge.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_off0000f582.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF582 18376 bytes
SHA-256: 81b7f66bb6d62b54ea7ea6e625e90432a648b94265e1f5c8a9cb5a10465f6025
font_01_sfnt_off000124d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124D2 10584 bytes
SHA-256: 88ac20801fe268e254f0dc07e0fe8ce087b65a7b94bd7f3a3ebf3e163c60039d
font_02_sfnt_off00013cc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CC2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1