Malicious PDF — malware analysis report

Static analysis result for SHA-256 d98a959e713d3be4…

MALICIOUS

PDF

103.2 KB Created: 2021-06-27 02:15:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4529490a5cebf1527015e9c334c02fa1 SHA-1: 7770da1e44a7701f3148eda82f381aee02f4958b SHA-256: d98a959e713d3be4cd73c0a5e33da5a656fc6c5f135301ffae3c4afeb9fe8be0
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file detected as malicious by ClamAV and an ML classifier. It contains embedded JavaScript, which is a common technique for executing malicious code within PDFs. The file also exhibits characteristics of a link farm, with numerous URLs pointing to potentially compromised websites, suggesting an attempt to redirect users to phishing sites or download further malware. The presence of embedded JS and the link farm structure strongly indicate a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9934

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/44268333815.pdf
    • http://canxetaianhduc.com/images/file/54971111535.pdf
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16076552ceaf36---kimikosonodimobe.pdf
    • http://ambvet-trefontane.eu/userfiles/files/bikonan.pdf
    • https://erinmillssmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/fv5vigsc3f89956ugvmmmakft7/foxegonedigozipep.pdf
    • http://www.tecnotrefg.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a3d41d51e3c---43811279056.pdf
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/csnoqp4qmijb3drj70dcjbfjpi/ruxurasoja.pdf
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083ca4d3bf6c---wolizijizinew.pdf
    • http://bright-inter.com/file_media/file_image/file/13024318336.pdf
    • https://internationalmedia.com/userfiles/file/wezurapiv.pdf
    • http://labonscafe.com/userfiles/51664310046.pdf
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ba42b7da06e---puxewewakifapovupaxi.pdf
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/1607f5fa13a1cc---medemopilipibetamiwudib.pdf
    • http://sshs61.com/clients/6/60/60e739d5a8cf4a6710e4f064fd99417d/File/81219011158.pdf
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/k8cjl6u4bc0vqqvn2qfvs6h9jm/32570674902.pdf
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/va2ua241rah91m09fhs31nitg4/28363433710.pdf
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/e8f6efd312265ac3e1bb909941f802c3/5546947920.pdf
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/59217263801.pdf
    • http://to-kajihan.net/js/upload/files/15168870316.pdf
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8e6072d7bf---48846634106.pdf
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084a4214df51---57178574172.pdf
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e5b76dd70b---98520973611.pdf
    • https://area34.info/wp-content/plugins/super-forms/uploads/php/files/m2rbib0qf5v423t28q88k1eu61/57405462336.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=meaning+of+comprehensive+in+telugu
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011a46.bin
14e82713ab6c023badd46474178a5cd60ea2ad97f1f40ea3ff00f5050ad0e33b
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A46 11088 bytes
font_01_sfnt_off000133f5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x133F5 16792 bytes
font_02_sfnt_off00014c07.bin
a9358817aa02000c1213b2a42e3b83e27d1ad9a5b743b221bf0fa27c6b9bd3cf
pdf-font-stream PDF embedded font (sfnt) at offset 0x14C07 26692 bytes