Malicious PDF — malware analysis report

Static analysis result for SHA-256 bfd36157dda9038f…

MALICIOUS

PDF

78.3 KB Created: 2021-09-19 20:08:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 698c7bcf502af200d84cd38efdf2ea8d SHA-1: e9f0942878e563af65d2e0cae68b460ffe788afb SHA-256: bfd36157dda9038f37674ec6a2d58f20af9f7dc675a2ac22b5fbad75ebf47a18
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous external URLs, many of which point to disposable hosting or compromised CMS upload storage, suggesting a link farm designed to redirect users. The presence of these URLs and the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicate a phishing or malware distribution attempt, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://nomylo.ru/uplcv?utm_term=poco+x3+system+update PDF link annotation
    • https://pecintajp.com/contents/files/gotetozemajozemak.pdfIn PDF document text
    • http://dennehylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/puperabodipeja.pdfIn PDF document text
    • http://jullien38.com/ressource/site-image/files/9884569793.pdfIn PDF document text
    • http://nanopena.cz/upload/file/57226341136.pdfIn PDF document text
    • https://holcom-solar.com/webroot/img/files/78394689218.pdfIn PDF document text
    • https://ebal.ro/app/webroot/files/userfiles/files/kakiwabaxejajem.pdfIn PDF document text
    • http://www.sanjuktabanerjee.com/fckimages/file/pofofu.pdfIn PDF document text
    • http://machinesupplier.cn/data/product/file/202197_162135_491.pdfIn PDF document text
    • http://muszempilla.com/files/file/90550558605.pdfIn PDF document text
    • http://szyqjsj.com/UploadFile/file/20210903085746404.pdfIn PDF document text
    • http://vandientuchinhhang.com/upload/files/15458544220.pdfIn PDF document text
    • http://bonsite.nl/phpcmsys/file/zusepos.pdfIn PDF document text
    • https://quanghuydulich.vn/img_duhoc/files/gugezomix.pdfIn PDF document text
    • http://www.likoda.com.tw/upload/ckimg/files/vozid.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/161414b226d4b4---zubizikug.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/16140e50e8fb9e---wuxexogojenuw.pdfIn PDF document text
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/01556eed8e8ac40d94759cd03077a566/sopaveruloximu.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/317953e55ef703cfdb849101c4abb02e/rekaboxaronovadogewa.pdfIn PDF document text
    • https://generalaudit.pl/eurostyl/photos/file/ritirowozapegezoz.pdfIn PDF document text
    • http://ranaghatpchsschool.org/userfiles/file/damovuwekeduwirad.pdfIn PDF document text
    • http://antracit.topmebli.com/content/xuploadimages/file/govonawelerazufazifozu.pdfIn PDF document text
    • http://mikailang.com/userfiles/file/20210901165641_755676436.pdfIn PDF document text
    • http://findmecakes.com/userfiles/files/jiwaxojixozadi.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_off0000ccdd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCDD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e4f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4F4 10824 bytes
SHA-256: 43aca36df204920b573246b8342774084163c49895aaf8b4b43a5729d16c2862
font_02_sfnt_off0000fe17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE17 17692 bytes
SHA-256: 550439c78d561853c609ad586169bbee7c6e378dc6ce6cc32a478da627ebc67c