Malicious PDF — malware analysis report

Static analysis result for SHA-256 e8cda3caf2d51dfa…

MALICIOUS

PDF

80.4 KB Created: 2021-09-20 16:03:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 7c30d2262daccc82ac3857dc736dfef5 SHA-1: 307adf7419bc4b45055d7d2903c7695d4d418232 SHA-256: e8cda3caf2d51dfa1f2a264afbb20ddf7821b931719a039b3aa40ea4bd40a560
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://synerhu.ru/uplcv?utm_term=junooniyat+full+movie+online+free PDF link annotation
    • http://nakamurasangyou.jp/app/webroot/uploads/files/82182687600.pdfIn PDF document text
    • http://hitelesen.com/userfiles/file/muwibisuxirapomoroxuzeseg.pdfIn PDF document text
    • http://smsalumni1971.com/apadmin/uploads/userfiles/files/bijikitobo.pdfIn PDF document text
    • https://astoriareiki.com/wp-content/plugins/super-forms/uploads/php/files/3621af854ff048c23b41cb431d77ab44/97321291978.pdfIn PDF document text
    • http://ckudzcssffhhj.handysociality.com/upload/files/76559927455.pdfIn PDF document text
    • http://bhttourist.com/upload/fckimagesfile/60641906715.pdfIn PDF document text
    • http://cosmoscm.com/contents/files/88683600150.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16145624c4dc17---31165669248.pdfIn PDF document text
    • http://dagmar-e.de/userfiles/file/guzatowuvovakiwugi.pdfIn PDF document text
    • https://arerp.kr/data/file///busilapalotiwebalukodar.pdfIn PDF document text
    • http://turbotechnik24.de/userfiles/file/41095758513.pdfIn PDF document text
    • https://samowar.me/userfiles/files/3859304149.pdfIn PDF document text
    • http://rockhouseschool.com/rockhouse/uploads/files/lumimugebonebawolivibum.pdfIn PDF document text
    • http://master-br.ru/img/file/43974314285.pdfIn PDF document text
    • https://ifbscalidad.eus/files/galeria/files/4102229220.pdfIn PDF document text
    • http://www.plain-pied.com/editeur/ckfinder/userfiles/files/41894023221.pdfIn PDF document text
    • https://francois-daulte.com/ckfinder/userfiles/files/75593801869.pdfIn PDF document text
    • https://needlugs.com/userfiles/files/61335900614.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16131ddf9a95ca---jukefalapibegitisuvili.pdfIn PDF document text
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1613cd78ef3f3c---71713989565.pdfIn PDF document text
    • http://theprojectmanagement.guru/cote_dor_import/admin/ckfinder/userfiles/files/ragelis.pdfIn PDF document text
    • https://rtaadmin.mrv-educationservices.com/content_file/files/4784328740.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_off0000d859.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD859 17076 bytes
SHA-256: a94425e20f2166b13ccbdcc2e551d28bbdf38b3c7ada67189de47c401efa9baf
font_01_sfnt_off0001042a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1042A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011c41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C41 10480 bytes
SHA-256: ff5ba9949f6d3b72c26d537a3ea500b639546be8e4a66fe191df2238004eac55