Malicious PDF — malware analysis report

Static analysis result for SHA-256 7effbf0daec87335…

MALICIOUS

PDF

74.4 KB Created: 2021-09-05 12:48:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7637fae40f69f06cfc9261e4695868cc SHA-1: d53923c7d63c087e8d200a6ca14c0654e35b07e6 SHA-256: 7effbf0daec87335fde45bc4c32b98db941fe3c2aa2105f074a07a8539f33014
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be associated with compromised content management systems or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The file's structure as a link farm suggests an attempt to obscure the ultimate destination and evade initial detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://allytemp.ru/uplcv?utm_term=diccionario+larousse+gastronomique+pdf PDF link annotation
    • http://albatrossmrn.com/konadnew/userfiles/file/17996701079.pdfIn PDF document text
    • https://jamurgoreng.net/contents//files/57664581306.pdfIn PDF document text
    • https://bindazzled.com.au/wp-content/plugins/super-forms/uploads/php/files/31ce298df7def0cdab637dcc93b262fa/94235258376.pdfIn PDF document text
    • https://khotelmarket.com/FileData/ckfinder/files/20210607_3E144A26EA4F057A.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/5aef6a7b568d1e458d5913bf91a39a46/nelimurotakoda.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160ee55aec278f---kiriwire.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606d15297575f---41002404793.pdfIn PDF document text
    • https://biocoils.com/img/file/3738931685.pdfIn PDF document text
    • http://udmvdpo.ru/images/files/42712810482.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/161030c3c8fcfb---25220711532.pdfIn PDF document text
    • http://inwallendorf.de/userfiles/file/88898469513.pdfIn PDF document text
    • http://boxshop.mn/userfiles/files/62026795392.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608840201a8c0---fonojameman.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a7320730209---70367260923.pdfIn PDF document text
    • https://khangle.vn/uploads/images/files/weverutonofeleluwaxu.pdfIn PDF document text
    • http://autoscuolecasetta.it/userfiles/files/fujakogukuxibotaxenapexax.pdfIn PDF document text
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/16097d1eb8857e---35522329614.pdfIn PDF document text
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16073584278c2f---pititekesofi.pdfIn PDF document text
    • http://xn--o79av69abka850ab6c.com/upload/file/202106111412282496.pdfIn PDF document text
    • http://musicpark-live.de/userfiles/file/nukuruvatuforiw.pdfIn PDF document text
    • http://www.alexgis.com/siteuploads/editorimg/file/lanuxexarekejabaroxejiw.pdfIn PDF document text
    • http://atonoserver.com/userfiles/file/barufuro.pdfIn PDF document text
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/f85c7e7b82f23da26527eab16798ac9b/fiduzomajenukimalif.pdfIn PDF document text
    • http://cancunday.com/travela/img/files/kejerufofabomoladidowux.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_off0000bb5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB5F 17664 bytes
SHA-256: 8732b315c72143d13d649e96783527643196a7a9cbd66530ef77e141278598f9
font_01_sfnt_off0000e99b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE99B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000101b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101B2 11212 bytes
SHA-256: f612f17856f325481b858c0ffa03b0d9fefff712c1a5a5ac1afe4497e8a2b1a2