Malicious PDF — malware analysis report

Static analysis result for SHA-256 ffc656bbc63d6309…

MALICIOUS

PDF

84.0 KB Created: 2021-09-16 13:19:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 01ed92699bc9e59d43456cbe2a233839 SHA-1: 59844e58c3e4cf6dd4a2455d06f5b7530a28dfdb SHA-256: ffc656bbc63d63093f78ed5536020938be7cd3e38d66d0c2a9d08e0f083d102d
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as a phishing trojan. It contains numerous links, many of which point to compromised CMS upload storage or disposable hosting, suggesting an attempt to lure users to malicious content. The document body is heavily obfuscated and unreadable, providing no direct clues about its specific purpose beyond the link farm heuristic.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://akcjonariusz.com/UserFiles/file/vivefutiforusuferoku.pdf In PDF document text
    • http://golfproradost.cz/webpagebuilder/ckfinder/userfiles/files/43736219059.pdfIn PDF document text
    • https://clinicaalcantara.es/sites/default/files/userfiles/file/kezirovogomitowov.pdfIn PDF document text
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16133dbad53d17---girilomawatozijujino.pdfIn PDF document text
    • http://leoclubmarsala.it/userfiles/files/kaxonezobitokexajudu.pdfIn PDF document text
    • http://occahomesearch.com/userfiles/files/71269757504.pdfIn PDF document text
    • http://technimexvn.com/images/ckeditor/files/sulesutijewar.pdfIn PDF document text
    • https://www.ijmsir.com/ckfinder/userfiles/files/99020061817.pdfIn PDF document text
    • http://creationart.hu/files/file/8905330581.pdfIn PDF document text
    • http://carbonelite.ru/file/reruzuzagezowu.pdfIn PDF document text
    • http://newbusan.net/FileData/ckfinder/files/20210911_F5193DE2BFBD6959.pdfIn PDF document text
    • https://manhalhealing.com/userfiles/file/40782792873.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/16138621d89471---66885506288.pdfIn PDF document text
    • https://andana.us/files/files/83819489371.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161408f4bc004d---vumiv.pdfIn PDF document text
    • http://katela.net/userData/board/file/16606192613.pdfIn PDF document text
    • https://newtech-utm.pl/userfiles/file/nijusajagonobulijav.pdfIn PDF document text
    • https://b7b.reviewz.eu/app/webroot/files/userfiles/files/pifisotexu.pdfIn PDF document text
    • http://irinabailey.com/upload/files/19768716055.pdfIn PDF document text
    • http://1night2day.com/ckupload/files/20684697620.pdfIn PDF document text
    • https://vmwarts.com/ecovic/file/28772517472.pdfIn PDF document text
    • http://spartaksedlec.cz/spartaksedlec/userfiles/file/nuxirumasosuzaniko.pdfIn PDF document text
    • http://www.mattig-accounting.bg/fisiere/file/turabivowizamefoxubobili.pdfIn PDF document text
    • http://yugreat.com/filespath/files/20210903160220.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=cool+android+games+freePDF 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_off0000e50a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE50A 17664 bytes
SHA-256: cdc0b76674541b8171ecf208e6638390aec72865f68865e04dc7daaf6a713dd4
font_01_sfnt_off000112ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112BA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012ad1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AD1 10628 bytes
SHA-256: 1a325aefb391c2036ec5c1fa175da65b4d52d2c7f3d86d9765c9ecc618b3af24