Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4a9258786072fe1…

MALICIOUS

PDF

78.8 KB Created: 2021-09-16 12:51:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: bb6fe34ee2c02dd3f5054807b87bbee1 SHA-1: a7ae7de2c71af049f7218ba9d869d07a60145172 SHA-256: e4a9258786072fe131e1ade37b8c987ad9898a3b87dd136c3e1549c44d2390d7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics indicates a strong intent to drive traffic to external sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://infrive.ru/uplcv?utm_term=blue%27s+clues+animals+in+our+house+watch+online PDF link annotation
    • https://bmw-zona.ru/uploads/file/muxusubajap.pdfIn PDF document text
    • http://kpotplace.com/uploads/files/xinitasakipusadaxexajejal.pdfIn PDF document text
    • http://jujucuisine.com/userfiles/file/97563114050.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16130be9f0eda9---perafirabotowemunuti.pdfIn PDF document text
    • https://kolkataangikar.org/ckfinder/userfiles/files/58011273832.pdfIn PDF document text
    • http://carnavaldemarbella.com/Senegal_5/Content/files/userfiles/file/xovidapedixinofurubiga.pdfIn PDF document text
    • https://habibitours.net/ckfinder/userfiles/files/lusuxizesi.pdfIn PDF document text
    • https://www.parquesanalbertohurtado.cl/ckfinder/userfiles/files/52176041824.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16133be40d87dc---bojadesufowujaniti.pdfIn PDF document text
    • http://petra-koparki.pl/Upload/file/65113457108.pdfIn PDF document text
    • http://denge.aero/upload/files/kojosefuro.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/b244313cfcd29f6256a211a0a0426f1a/tavuwafusumevinerateza.pdfIn PDF document text
    • http://integrotech.com/zdjecia/file/45341189619.pdfIn PDF document text
    • https://maturana.cl/upload/file/sewefovusado.pdfIn PDF document text
    • https://copacndg.com/images/uploads/files/zubapojenepexuxutu.pdfIn PDF document text
    • https://larrialdiak.es/files/galeria/files/folonidexebulapijuge.pdfIn PDF document text
    • http://harnettcountyhba.com/userfiles/file/makumuruxor.pdfIn PDF document text
    • http://sahamit.net/userfiles/file/vefafisoku.pdfIn PDF document text
    • http://ana-jsc.com/upload/files/53650057007.pdfIn PDF document text
    • http://jingluo.net/uploadfiles/files/pinajigaguvawosesusijiba.pdfIn PDF document text
    • http://patrickstaxi.fr/userfiles/file/54522839127.pdfIn PDF document text
    • https://prestinieurope.com/userfiles/files/68524193210.pdfIn PDF document text
    • http://ninda.vn/userfiles/files/75431932871.pdfIn PDF document text
    • http://globomax.eu/userfiles/file/gigifapeguveneruzaf.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_off0000cd8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD8F 17924 bytes
SHA-256: 27fbd2232b1b0ff1580dbb01859ebbd02587103027362c07ace8f72fe9e58ed0
font_01_sfnt_off0000fc1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC1D 10768 bytes
SHA-256: d95488d24b01b818576d3a50e00d132fdda5fe9915b9ef75fc68382ff1ea232e
font_02_sfnt_off000114d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114D5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1