Malicious PDF — malware analysis report

Static analysis result for SHA-256 4456de76f593dd63…

MALICIOUS

PDF

73.4 KB Created: 2021-09-25 13:02:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 05d74c50d9ba14320eb1ba515e4fd9d6 SHA-1: 00ead5cdcd4ce42e7e9636567dffb9b4296d995a SHA-256: 4456de76f593dd632a2ece11297b0ad61c6fc5cabfb9de17a6959aee518c3798
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs that form a link farm, likely intended to redirect users to phishing sites or download further malware. The document body is heavily obfuscated and contains metadata indicating it was generated by wkhtmltopdf, a tool often used to create PDF documents from web content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://wastran.ru/uplcv?utm_term=need+for+speed+no+limits+cheats+apk PDF link annotation
    • https://combrooncom.com/contents/files/xokejepebeso.pdfIn PDF document text
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/1tn8af0jt45qegnoc4f60la9u5/62016481465.pdfIn PDF document text
    • http://aerotherminsulation.com/userfiles/file/31282602640.pdfIn PDF document text
    • http://duet-czluchow.pl/userfiles/file/41655062736.pdfIn PDF document text
    • http://gpba.ge/admin/ckeditor/ckfinder/userfiles/files/67525381375.pdfIn PDF document text
    • https://tspinstruments.com/cache/fck_files/file/86918082625.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614ca0bb3c9f8---36311609077.pdfIn PDF document text
    • http://kidsjeodo.com/images/files/44318100508.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1614a25a500abf---sulixizux.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/16140494fc9310---7553942743.pdfIn PDF document text
    • http://guanzhuli.com/userfiles/file/jeropilo.pdfIn PDF document text
    • http://sherwoodonionfestival.com/ckfinder/userfiles/files/11983788414.pdfIn PDF document text
    • http://clinicaveterinariamontecchia.com/userfiles/files/89591924477.pdfIn PDF document text
    • http://lachambredechos.com/userfiles/file/80043371583.pdfIn PDF document text
    • http://moonlightmontessori.com/upload/files/fuxuwuve.pdfIn PDF document text
    • https://jogamiskolc.hu/ckfinder/userfiles/files/9239334495.pdfIn PDF document text
    • http://linuxnewyork.com/draft/media/teviwu.pdfIn PDF document text
    • https://biharlokmanch.org/userfiles/file/pubegev.pdfIn PDF document text
    • http://verduciautodemolizioni.it/userfiles/file/85714548107.pdfIn PDF document text
    • http://519pf.com/userfiles/files/roderomig.pdfIn PDF document text
    • http://voijin.com/userfiles/files/wadiwuvetedimilowur.pdfIn PDF document text
    • http://alessandrobelleseveterinario.eu/userfiles/files/10589550193.pdfIn PDF document text
    • http://onnetsolution.in/userfiles/file/roresonide.pdfIn PDF document text
    • http://www.mamafoundation.cz/ckfinder/userfiles/files/13357298525.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_off0000b3b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3B6 19448 bytes
SHA-256: 81117f59d4c760a2ccdec69d3600dbe2ad54c2eb03a84444fb3b9dca5772cd80
font_01_sfnt_off0000e698.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE698 10952 bytes
SHA-256: 9ae2e8ab49dd75a7a0ccab0635f77e8f4c367c0c9df1c2be0d751530a9c52752
font_02_sfnt_off0000ffcb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFCB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1