Malicious PDF — malware analysis report

Static analysis result for SHA-256 678a953874504637…

MALICIOUS

PDF

78.4 KB Created: 2021-09-19 09:31:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 619bcb06679b30552365997be181cc43 SHA-1: 536b69c3bcc6aef5505228e457a95b0519976626 SHA-256: 678a953874504637bd6eb05c7a48cf7812d015b82770aedca47d7d465ac555ff
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains embedded JavaScript and a large number of external links, many of which are hosted on compromised or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is likely used to facilitate the redirection to these malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 https://living-stone.lu/userfiles/files/retumo.pdf In PDF document text
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/8ef1a414356514decf2f10fd36a0ba76/jigikewut.pdfIn PDF document text
    • http://ahrestygz.com/userfiles/files/20210901_052938.pdfIn PDF document text
    • http://email-database.info/userfiles/file/85662703534.pdfIn PDF document text
    • https://at1-turbo-j3t.com/contents/files/jozasebuwakanuf.pdfIn PDF document text
    • http://elskenecologie.nl/files/zukedopazozegizikipo.pdfIn PDF document text
    • http://lagostena.it/userfiles/files/goxox.pdfIn PDF document text
    • http://torremaggiore.sitmap.it/files/files/butefikenaxidapiwumepave.pdfIn PDF document text
    • https://quizai.com/uploads/files/laduvagifu.pdfIn PDF document text
    • https://agri-mal.pl/userfiles/file/63962858311.pdfIn PDF document text
    • http://tlumacz-francuskiego.pl/userfiles/file/16902249241.pdfIn PDF document text
    • http://plovdivweek.com/app/templates/js/ckfinder/userfiles/files/24958084613.pdfIn PDF document text
    • http://enjoyisagenix.com/ckfinder/userfiles/files/xenaxikofisabopevaje.pdfIn PDF document text
    • http://amicalelaique-guyancourt.fr/ckfinder/userfiles/files/fuxatabijetan.pdfIn PDF document text
    • http://ricoconsultingattorney.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kalador.pdfIn PDF document text
    • http://weighlessthisyear.com/ckfinder/userfiles/files/bilojozuzunazowudakowe.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/161370b9a1fde6---nigenekuviva.pdfIn PDF document text
    • http://cherriestattoo.com/ckfinder/userfiles/files/62977179710.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613745887d48c---55849491568.pdfIn PDF document text
    • http://etyekilovarda.hu/userfiles/file/62742320126.pdfIn PDF document text
    • https://kildevangen.dk/files/lelarikeliwitixesokoruf.pdfIn PDF document text
    • http://lamay.de/userfiles/file/63232273322.pdfIn PDF document text
    • http://hanhthien.net/uploads/file/70125471820.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=spider+man+3+game+play+storePDF 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_off0000c77b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC77B 11096 bytes
SHA-256: 6bdf50c9d4bc1434411a93abf90105df17f8b890ffe25d86b64376af22032321
font_01_sfnt_off0000e11e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE11E 19124 bytes
SHA-256: 3683c4dc3d668e4cc9a05ee559ced2fdd4e5cbef68d1feadcb1ef16c95480b25
font_02_sfnt_off0001134a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1134A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1