Malicious PDF — malware analysis report

Static analysis result for SHA-256 6ee96f64b115e085…

MALICIOUS

PDF

73.0 KB Created: 2021-09-05 22:29:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 0770847b2b7d0a066c26454d42ede17d SHA-1: 9173e5dfd247f91570dd16ad98e4215923ef2f24 SHA-256: 6ee96f64b115e0853837d341e553f7341d8bc382a84ca8148b6cea6a9b6f20da
156 Risk Score

Malware Insights

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

The file is identified as malicious by a ML classifier and ClamAV, with the latter specifically flagging it as Pdf.Phishing.Trojan. Heuristic analysis indicates the PDF functions as a link farm, with numerous embedded URLs pointing to compromised CMS upload directories and disposable hosting domains. These links are likely intended to lure users to phishing or malware distribution sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a5d33d881c4---49544518879.pdf In PDF document text
    • http://burfel.ru/upfiles/files/72970957599.pdfIn PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081cc921a41b---rufegotutazenadosumefevo.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ca2d8fd2332---vozagugodob.pdfIn PDF document text
    • http://protok.pro/upload/files/34573727726.pdfIn PDF document text
    • https://neavocats.com/wp-content/plugins/super-forms/uploads/php/files/ab715837eb2f226cb57098d34d8971de/76111297285.pdfIn PDF document text
    • http://jdhs77.com/clients/58520/File/luxelularinev.pdfIn PDF document text
    • http://winecellarkeeper.com/ckfinder/userfiles/files/wudemez.pdfIn PDF document text
    • https://happyfun.tw/uploads/files/202109051510119366.pdfIn PDF document text
    • https://mintowncoffee.net/uploads/images/files/kumofasuj.pdfIn PDF document text
    • http://pulsarvn.com/media/ftp/file/49069702650.pdfIn PDF document text
    • https://dubigroup.com/admin/fckeditor/editor/filemanager/connectors/upload/file/27325542427.pdfIn PDF document text
    • http://xn--o39a91gvwm83kbsn.net/FileData/ckfinder/files/20210629_C5C1AC8D19D48D1B.pdfIn PDF document text
    • https://motelandratecuci.ro/userfiles/file/98866675684.pdfIn PDF document text
    • https://rubin2000-distribuitorshop.ro/userfiles/file/31100455174.pdfIn PDF document text
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/5b3dcde185e18e5f7c5c9423d93a2c1e/5298969213.pdfIn PDF document text
    • https://1877painters.com/FCKeditor/file/karewojas.pdfIn PDF document text
    • https://stratasphere.online/userfiles/file/gijagep.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=mitsubishi+pajero+2016+manual+pdfPDF link annotation
    • 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_off0000b529.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB529 11588 bytes
SHA-256: f76715455c306a131317580bb9841a4f0c3fb082d514cdf3f46b28765773a2a1
font_01_sfnt_off0000d04d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD04D 17756 bytes
SHA-256: 90affd8baeb7182a9fe0159509e910fee3eafea5b78fcdb617bf575f3fb4a532
font_02_sfnt_off0000fe47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE47 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1