Malicious PDF — malware analysis report

Static analysis result for SHA-256 77c95ecc4e0516dc…

MALICIOUS

PDF

82.7 KB Created: 2021-07-04 14:49:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 2466f4f52a947b750fd5f3e01a1e040d SHA-1: 6181051a2626c423c12b009d0e13a3e068013de5 SHA-256: 77c95ecc4e0516dc157fdce43f7905c1da4277f2bf245e1ec2b19e5a66997ef1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, specifically identified as a phishing or trojan distribution attempt. It contains numerous links pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URIs and the overall structure indicate an attempt to leverage these links for initial access, likely through spearphishing attachments.

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 https://pistant.ru/uplcv?utm_term=all+i+want+for+christmas+guitar+tab PDF link annotation
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ad99b8e1468---97289022746.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160cca06699e58---koseramowajawivofi.pdfIn PDF document text
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/6501d0cd28eecb314af4bbf0c4dbc3ea/suxulafesikoxabofake.pdfIn PDF document text
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/6eqmcrm01a84bi3lfljtdc0lkg/70669070633.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160adecbea084a---xinivuxekuwelaxewufokagov.pdfIn PDF document text
    • http://onestudent.dk/userfiles/file/wanosi.pdfIn PDF document text
    • http://robalton.es/Albums/images/file///13881637986.pdfIn PDF document text
    • http://southport1969.com/clients/861680/File/konawe.pdfIn PDF document text
    • http://stylist.in.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160dfd3312149f---dalumekaf.pdfIn PDF document text
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160db381b038d5---jagudu.pdfIn PDF document text
    • http://unsersohn.ch/images/file/14627842021.pdfIn PDF document text
    • https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/6f5e7abf1a7b449012d3570d67fba797/95880045798.pdfIn PDF document text
    • http://mxm-hosting.nl/img/editor/file/56782598344.pdfIn PDF document text
    • http://hilltoplancers1975.com/clients/13753/File/vofodoxekirexofa.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/160c8f7796ecbb---gosijojuwapedogatejip.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/001191aba27ce8f6d0cb305d3429c4fe/febasolatiretunojefuji.pdfIn PDF document text
    • http://aprendanow.com/wp-content/plugins/super-forms/uploads/php/files/e2085d1bdb63436391d6251eb35e8f18/fijuzajaxokuwuvolefef.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/hphmtl3u5dog6ats2b7banc0um/xetaga.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160c1c31817fa4---rodamezawepimudifoxedegol.pdfIn PDF document text
    • https://workinhotel.com/upload/fckfile/nemopo.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/2qnvpdse06ku3o99e68ar9bphk/73991709247.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608852b767e5a---21055055373.pdfIn PDF document text
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160beaf3251881---remepizareduvavu.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085747e6d208---budoxubuvasadelonafareni.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_off0000df83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF83 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f79a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF79A 10956 bytes
SHA-256: 4629351ecb8c8db64a436ca83b92912c3354f551538dec7ee52f74afcebad85d
font_02_sfnt_off000110e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110E8 17152 bytes
SHA-256: cf56d14241c9782494164f53e9438afbb2c999acb71a98defa7f25ad350823ab