Malicious PDF — malware analysis report

Static analysis result for SHA-256 849e86b108268ded…

MALICIOUS

PDF

82.3 KB Created: 2021-07-06 19:59:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 93ef45ca448a427ce994cf6acabdcdbe SHA-1: feb20568707222c4ce6a34572a373783aca42e49 SHA-256: 849e86b108268ded141b9e435d029c4db6751931567bed9b6a6c62236b7d028a
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs that point to compromised WordPress sites, suggesting it functions as a link farm designed to redirect users to malicious content. The presence of external URIs and link farm heuristics strongly supports a phishing or malware distribution attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://medvor.ru/uplcv?utm_term=never+alone+lady+antebellum+meaning PDF link annotation
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a962740b0b2---98806666477.pdfIn PDF document text
    • https://www.eziblank.com/wp-content/plugins/super-forms/uploads/php/files/sdu29amk4buioqeeui3hfsapn4/25499192164.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/26ba420070b893628d0e62173d0b06d7/73784058292.pdfIn PDF document text
    • http://www.vljainandco.com/userfiles/files/7623542504.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a0e1ce17468---kaziziloxuzidatiruwinagab.pdfIn PDF document text
    • https://legouic-peinture.fr/userfiles/file/rorus.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/160794f9b6aa45---siloxifotazubotifix.pdfIn PDF document text
    • http://uralinteh.com/uploads/files/90910329011.pdfIn PDF document text
    • https://laurallo.com/ckfinder/userfiles/files/64946376438.pdfIn PDF document text
    • http://congtyrongtien.com/upload/files/wiwas.pdfIn PDF document text
    • https://www.electriclighting.com/wp-content/plugins/super-forms/uploads/php/files/54bf579abfa6142f8f0fd10ca813d6f9/tefimijav.pdfIn PDF document text
    • https://b2cexpressdemo.com/userfiles/file/86312122583.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bce0ad829d7---lagoxulovof.pdfIn PDF document text
    • http://marmaraisg.com/images_upload/files/17979879878.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076a5173e50f---10219201058.pdfIn PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/66797336cb3c2b76872c39a2496837c5/35974086847.pdfIn PDF document text
    • http://darienhigh69.com/clients/866565/File/bakaro.pdfIn PDF document text
    • http://minicabii.com/survey/userfiles/files/tugilobojirawiwefav.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5b3eb81861---jefufewefova.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-7-5/20210705162153686853.pdfIn PDF document text
    • https://cungcapthitdetuoi.com/app/webroot/files/images/pages/files/tubexaxu.pdfIn PDF document text
    • http://risme.vn/files/bezuwo.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160833672e3f20---zevebulujunoritudekupati.pdfIn PDF document text
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/2e6cd408da2e3ca9717c4cfe56d94f05/67109147397.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b129d44120---totabutuzufugatitazevo.pdfIn PDF document text
    • http://guanzhuli.com/userfiles/file/gijexubawaronelogezezik.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_off0000df68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF68 10820 bytes
SHA-256: b5f4050385bbe8affd7fbb0b7769a9e3fbd116dd1fc3b6b5f7e69d98a9879918
font_01_sfnt_off0000f81c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF81C 17244 bytes
SHA-256: 420951d379e7f5d2d78dcc1729b24ca6c06f4afde36fda3186e0ccc63a356e4d
font_02_sfnt_off00012347.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12347 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1