Malicious PDF — malware analysis report

Static analysis result for SHA-256 dacdba8643379df4…

MALICIOUS

PDF

81.3 KB Created: 2021-09-11 15:59:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 1d6bb9375a2c450c560c4020b6690ca4 SHA-1: da4a7bddd01e88ad69c11a939e5cf3a5179b6485 SHA-256: dacdba8643379df4cbde7bd97e7220903983f426af7c307d0d850a20f04045aa
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or malware distribution intent. It contains numerous embedded URLs pointing to compromised websites and disposable hosting, suggesting it functions as a link farm to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://drafthe.ru/uplcv?utm_term=layarkaca21+cinema+xx1 PDF link annotation
    • https://costarica4d.com/contents/files/35809546806.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/4cvrrfj5bchob5tvc4n9f46h73/xagufiwikifupomid.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613048d3bae01---dikibupiruw.pdfIn PDF document text
    • http://zartmobilia.com/userfiles/file/20210910113543.pdfIn PDF document text
    • http://apsons.eu/files/file/21862985511.pdfIn PDF document text
    • http://www.kotolantopeni.cz/files/5093379773.pdfIn PDF document text
    • http://doudou.tw/userfiles/files/67155924190.pdfIn PDF document text
    • http://acmemask.com/upfiles/editor/files/905555412.pdfIn PDF document text
    • http://krajinar.cz/soubory/files/tamevexokute.pdfIn PDF document text
    • http://www.rajpuc.pl/pics/file/segif.pdfIn PDF document text
    • http://sushibelovo.ru/files/tegojedinos.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613be4475b6c4---ladomevitofa.pdfIn PDF document text
    • https://satyawatioverseas.com/userfiles/file/87848666448.pdfIn PDF document text
    • http://ulrike-mayer.de/userfiles/files/fiboxomobajazujuj.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135e72370b39---22419115615.pdfIn PDF document text
    • https://hometeamcorp.com/images/usr/76878009304.pdfIn PDF document text
    • http://p-itos.net/admin/userfile/image/file/37567038458.pdfIn PDF document text
    • https://10fci.org/userfiles/file/98754994185.pdfIn PDF document text
    • https://ddc-touggourt.dz/ar/files/retuko.pdfIn PDF document text
    • https://nichecnk.leaddeehub.com/userfiles/files/gutabovaw.pdfIn PDF document text
    • http://cinstech-inspect-survey.com/fckeditor_userfiles/file/63563747006.pdfIn PDF document text
    • http://tungalag.mn/userfiles/files/bimonosazidigexujan.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/16133d6e025cd1---99546232366.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_off0000d9a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9A5 10396 bytes
SHA-256: d811723c001ae3ed65d30e056b12ef8aa7924ee5d71049e7da766b84fde8a873
font_01_sfnt_off0000f13f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF13F 17848 bytes
SHA-256: 5ced6def6a5686a86b746529728a63d6a9b4c236085d2ae509c229801206c977
font_02_sfnt_off00011feb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FEB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1