Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b15316f779dda54…

MALICIOUS

PDF

70.8 KB Created: 2021-09-26 15:12:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2ead4b80a48dc1ca4f99be544c515f6f SHA-1: 5f46c1487a002a6dc08a41a620ed9ce07e271ca2 SHA-256: 3b15316f779dda5418dfb72e725f7ca750408e20d6480a31f7242cfecede8f50
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, which is often used to redirect users to malicious websites. Several heuristics indicate the PDF is part of a link farm, with many URLs pointing to compromised CMS uploads or disposable hosting, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://huntic.ru/uplcv?utm_term=parasite+full+movie+with+english+subtitles
    • https://alirezamirmohammadi.com/images/upload/files/wanenoniwewinudosedobolu.pdf
    • http://softtox.pl/new/userfiles/file/pakapavejojanuvexoxuke.pdf
    • http://ever0036.com/assets/uploads/ckedit/files/20210907212253.pdf
    • https://chatsystem.site/js/ckfinder/userfiles/files/50322211621.pdf
    • https://nieruchomosciturystyczne.eu/files/file/sajuxedidusamenovekonifa.pdf
    • http://kxzyjy.com/CKEdit/upload/files/tesoliwavukijadilusanupa.pdf
    • https://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/deda0cedb56c8cdfc7317bb2ce73a8fe/18839467313.pdf
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1613185f0c57fe---79483677986.pdf
    • https://rippa.pt/files/file/71648012218.pdf
    • https://sofupingame.net/calisma2/files/uploads/78735128625.pdf
    • http://selfmadefilms.nl/userfiles/files/xikixerutekaf.pdf
    • http://narzedziascierne.eu/Upload/file/91595064560.pdf
    • https://campfun.myhost888.com/upload/ckeditor/files/72660982695.pdf
    • http://tries.cz/media/images/upload/file/susurovuz.pdf
    • http://thainightjob.com/ckfinder/userfiles/files/sesozutawuxegoverabi.pdf
    • https://indicaperu.com/userfiles/file/8781220657.pdf
    • http://tunecharts.com/userfiles/file/wetapapepixu.pdf
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/161494db9e89c0---33130377222.pdf
    • http://avtosfera28.ru/userfiles/file/12874936571.pdf
    • http://pensionpoint.cz/userfiles/files/72353918315.pdf
    • http://asr-net.ru/uploads/files/relufofab.pdf
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161333e264367b---4462552361.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b11f.bin
e7a5b95fd15436685bd66c09776a3bc87a41517e81f103fb29324e8d42d7da78
pdf-font-stream PDF embedded font (sfnt) at offset 0xB11F 16720 bytes
font_01_sfnt_off0000db88.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB88 16792 bytes
font_02_sfnt_off0000f39f.bin
01ca3709a0ea6bfc53aae49479df1e1668ab592374d871d0d377cae10aa80277
pdf-font-stream PDF embedded font (sfnt) at offset 0xF39F 11056 bytes