Malicious PDF — malware analysis report

Static analysis result for SHA-256 de2e859ff74df070…

MALICIOUS

PDF

71.4 KB Created: 2021-09-27 05:31:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 7248a3814932551a8976bb2d3aa3ec82 SHA-1: 08237738e842110389fe93523a878609481e121c SHA-256: de2e859ff74df070715fb37bee5ed7fa4804cf094837ef1e5f60ba1c13a7d125
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for exploiting PDF vulnerabilities or redirecting users. Multiple heuristics indicate the PDF is part of a link farm, with many URLs pointing to external sites, some hosted on compromised WordPress installations. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://smidgel.ru/uplcv?utm_term=what+to+write+when+you+send+a+cv PDF link annotation
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16139eb92babda---89786806718.pdfIn PDF document text
    • https://codefon2.solar-napkollektor.hu/js/ckfinder/userfiles/files/wuxoratuwos.pdfIn PDF document text
    • http://tweddlefoto.com/files_contenidos/upload/files/52934634457.pdfIn PDF document text
    • http://nowator-zpu.pl/userfiles/file/gimijo.pdfIn PDF document text
    • http://biemmecommerciale.eu/userfiles/files/bujosimume.pdfIn PDF document text
    • http://asvpp.fr/pdf/nevis.pdfIn PDF document text
    • http://mebizstekla.ru/userfiles/file/jabafosumidijawoxo.pdfIn PDF document text
    • https://dzido.pl/userfiles/file/69203372513.pdfIn PDF document text
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614b3b4c7aeb0---53973735141.pdfIn PDF document text
    • https://angkortaxiservice.com/userfiles/file/76615429836.pdfIn PDF document text
    • https://shivajigrihnirman.com/singhania/downloads/file/xanewimipulesubafimis.pdfIn PDF document text
    • http://tecsun-moscow.ru/docs/file/nebozadate.pdfIn PDF document text
    • http://hidrometa.com/images_upload/files/31083381282.pdfIn PDF document text
    • https://ctcitsupport.com/media/files/27158508747.pdfIn PDF document text
    • http://icltindia.in/userfiles/file/5171252656.pdfIn PDF document text
    • http://piotrkowska77.pl/zdjeciafile/rejozixex.pdfIn PDF document text
    • https://cafesca.mx/ckfinder/userfiles/files/21843161022.pdfIn PDF document text
    • http://geologicatoscana.eu/userfiles/files/kawoxemok.pdfIn PDF document text
    • http://healthywithhart.com/res/file/93208645000.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/gowunajop.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144ba10552df---fabixaverisalavewipeduwa.pdfIn PDF document text
    • https://festival-bg.com/media/ckuploads/files/58830150417.pdfIn PDF document text
    • http://auto-spec.ca/fck/file/vaxonisaxi.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_off0000b205.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB205 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ca17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA17 17156 bytes
SHA-256: 2b064e52e442844681a477d3bd665844a91ad5d99b717986d436ee70f253551a
font_02_sfnt_off0000f558.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF558 10780 bytes
SHA-256: 4a9d405db637fadd67d5746cbf998118cf19be6fc41ae79ad5954d56dab8d46d