Malicious PDF — malware analysis report

Static analysis result for SHA-256 2043f843c53c0925…

MALICIOUS

PDF

72.5 KB Created: 2021-09-08 03:51:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e5941541f01b416d23b0b0e7698a820f SHA-1: 3acec54b48150e484dc47813063247fbc295df84 SHA-256: 2043f843c53c092564f29306369102e65dcd94f8c0a9e914debe7f6858fc3cd7
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. Heuristics indicate it functions as a link farm, with multiple URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious content. The document body is heavily obfuscated and unreadable, providing no further context on the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://dalnoboy.com/data/filestorage/upload/files/59348690098.pdf In PDF document text
    • http://mai-colle.jp/userfiles/file/61842618787.pdfIn PDF document text
    • https://alcoquimicos.com/ckfinder/userfiles/files/dimagepurevonikiniwenoxif.pdfIn PDF document text
    • http://alpha-th.com/userfiles/file/75758375253.pdfIn PDF document text
    • http://oldtimerclub-thueringerberg.at/images/file/8475300375.pdfIn PDF document text
    • https://angkoronetour.com/userfiles/file/bikabefepevax.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/moxufuwabebukeramud.pdfIn PDF document text
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/3312b07e3166411f329ce2a009f4e172/rirebosovomajose.pdfIn PDF document text
    • http://bioscipublisher.com/files/upfiles/file/pedame.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba77ac50735---roxelovuzowizugikazip.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/160719e5d0057f---riduwovukimenazubuzawex.pdfIn PDF document text
    • http://co-wemart.com/careeruserfiles/file/55934666412.pdfIn PDF document text
    • http://amdind.com/userfiles/file/44986745412.pdfIn PDF document text
    • https://neavocats.com/wp-content/plugins/super-forms/uploads/php/files/9ca4c120bc77fc902e6d965599ce5da9/32751437663.pdfIn PDF document text
    • http://www.dereformasenalicante.com/archivos/files/xojakikaji.pdfIn PDF document text
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/oqdnfpcthvfuch74m9gudjfdq5/34595849445.pdfIn PDF document text
    • http://axiomestates.com/userfiles/file/5848872480.pdfIn PDF document text
    • http://bi-acaovo.com/upload/files/kemuke.pdfIn PDF document text
    • https://jmtours.co/aym_image/files/87425608711.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d8a24aae130---74804324724.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=flight+stability+and+automatic+control+solution+manualPDF 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_off0000b7e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7E4 16656 bytes
SHA-256: 8de56a933d7cc141596704980ab347a759921b8e5198a4c282a75c27959eaf42
font_01_sfnt_off0000e31c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE31C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fb33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB33 11016 bytes
SHA-256: b9aa84e06697d064725a00ee453aa5dc82fe529d66f28252e5c9d67af50199dd