Malicious PDF — malware analysis report

Static analysis result for SHA-256 4857fcb35c06b196…

MALICIOUS

PDF

82.1 KB Created: 2021-09-18 08:44:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 3eb93d0c12cb97ee6863fcac1ef9c767 SHA-1: 1dd0d694ef76ba8b298b7aa8104c76fe528eeb87 SHA-256: 4857fcb35c06b196174b1b02d4642e666d8bd1fd933cc280b40add5fd916cc69
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised websites or link farms. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or redirecting users to malicious content. The presence of link farm heuristics suggests an attempt to obscure the final destination or leverage compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://e-sportis.com/images/upload/kaxefipozopifi.pdf In PDF document text
    • http://toanlinh.vn/upload/files/tevirebamo.pdfIn PDF document text
    • http://umhouses.com/uploads/files/79003485117.pdfIn PDF document text
    • http://savytrading.com/userfiles/file/kunafoj.pdfIn PDF document text
    • http://inica.org/files/file///mifuditativitinexuvavux.pdfIn PDF document text
    • http://obchodsezlatem.cz/upload/files/pujakigafidigon.pdfIn PDF document text
    • http://vizcsap.hu/files/file/resot.pdfIn PDF document text
    • https://astoriareiki.com/wp-content/plugins/super-forms/uploads/php/files/7a734cf67765a1ae1ffb50243747c941/3386847049.pdfIn PDF document text
    • https://mandarinusa.com/userfiles/file/1630914408.pdfIn PDF document text
    • https://jpjplumbingandheating.com/FCKeditor/file/76467806123.pdfIn PDF document text
    • http://marjoleintje.nl/include/userfiles/3801398808.pdfIn PDF document text
    • https://maffart-guy.com/userfiles/file/vudibufanisajalanopalem.pdfIn PDF document text
    • https://artasedanasingaraja.com/uploadfck/file/26927757686.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/16142ec94262dc---bakapatozeka.pdfIn PDF document text
    • http://kiapelhrimov.cz/UserFiles/File/42936104944.pdfIn PDF document text
    • https://campfun.myhost888.com/upload/ckeditor/files/kedikelevapojofekoxi.pdfIn PDF document text
    • http://laihoawedding.com/app/webroot/upload/files/55520775013.pdfIn PDF document text
    • https://ebal.ro/app/webroot/files/userfiles/files/75128940350.pdfIn PDF document text
    • http://mamaskitchenorder.com/uploads/files/2839266976.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/5cd364a4dc23fb8b00d8aa1daf11342c/nagizunevubuwozisogawoj.pdfIn PDF document text
    • http://eviljoy.com/UserFiles/File/fimixo.pdfIn PDF document text
    • http://smlstripedbass.com/home/rock/public_html/ckfinder/userfiles/files/52006727203.pdfIn PDF document text
    • https://dycmc.com/DATA/upload/files/202109042234424501.pdfIn PDF document text
    • https://cs-nippon-cp.com/mailmagazine/upload/files/78412205643.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/4172ad2a1396d7d024a064e8aa3143d4/jawonolatadanoke.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=what+does+android+stand+forPDF 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_off0000de31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE31 10400 bytes
SHA-256: 02b8acfb819c1fa08ad74188b2768b626ee269c382fa4aa24be7502e3bf51eda
font_01_sfnt_off0000f5ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5AD 17368 bytes
SHA-256: 554218ad0d6d0056eafa4bfa20e54f8e94f65e49ada8db2cf18db248103c303f
font_02_sfnt_off00012300.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12300 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1