Malicious PDF — malware analysis report

Static analysis result for SHA-256 e7fb6a8ada5e1590…

MALICIOUS

PDF

71.1 KB Created: 2021-09-19 10:36:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 44c46ec1ebe01dbd6c933be364aee7a6 SHA-1: 98deb689c87b62f208988f8bfe6fd845b45d65ef SHA-256: e7fb6a8ada5e1590033639bdd6cd1f0c83373ef01814013673a02d7acc2795bd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads and disposable hosting, indicating a link farm designed for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were directly extracted, the nature of the embedded links and the heuristic firings point towards a phishing or downloader attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://kiemtoandongnghi.com/public/plugins/ckfinder/userfiles/files/83634345584.pdf
    • http://xn--2e0b95unoa536adofm5h.com/userfiles/file/kelofuvifitotilefolu.pdf
    • http://thefertilizerproductionline.com/d/files/rejuk.pdf
    • https://indiansabroad.uk/userfiles/file/89648434673.pdf
    • http://dighakanchaninternational.com/FCKeditor/file/64466103454.pdf
    • http://wyadonline.com/userfiles/file/fegisalagurapugitoraje.pdf
    • http://apex-architect.ru/images/file/49725713226.pdf
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613fb8942a5fb---26073424476.pdf
    • https://wonwon.taipei/photo/file/50926811242.pdf
    • http://pure-chiral.com/upload/files/dubedekijujiwuvabokane.pdf
    • http://pokrowce-ochronne.pl/Upload/file/49591800213.pdf
    • http://irk-yoga.ru/upload/files/63309659473.pdf
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/161464e3250949---pojajegukenemitanisizikuf.pdf
    • https://mzr-avocats.com/buddha/ckfinder/userfiles/files/miboxajedumegilorop.pdf
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/161335fb71218b---90975848384.pdf
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613d1f9f19ee1---podagojolugukukeger.pdf
    • http://xn--9p4b29dncp2cc6y.net/upload/fckeditor/file/gunesuj.pdf
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ed7204e01b---47819067005.pdf
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/5d713d6f5a7cac0bf78671f903bb64c7/xivotupufimudulusezinato.pdf
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/16141c9d0ed5e1---60059887062.pdf
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/31fjs4avrhed01a786fejma902/2163052869.pdf
    • http://lawyergz.net/uploadfile/files/261540888.pdf
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/5aebd984000f8001b086ebb552c69edb/wadevosozetebisejowu.pdf
    • http://spellenindex.nl/images/uploads/rabewafetepe.pdf
    • https://auto-rujo.com/images-editor/file/wedosibubolok.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=tomcat+outofmemoryerror+java+heap+space
    • 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_off0000b87b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB87B 16792 bytes
font_01_sfnt_off0000d092.bin
958e81f772090a40a02dbf29aed4d19dbdf513ef73f3ecedf1605f1a0d62be7f
pdf-font-stream PDF embedded font (sfnt) at offset 0xD092 10876 bytes
font_02_sfnt_off0000e9d6.bin
350b7bbe4c42db1e787624569649501ecfc5df5e73d39ea67ddee91905313993
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9D6 14676 bytes