Malicious PDF — malware analysis report

Static analysis result for SHA-256 5814cfbfdfa99aab…

MALICIOUS

PDF

79.2 KB Created: 2021-09-12 15:24:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 4ab56902095e38ecafe741a35a7a08aa SHA-1: 598c9cb2271afafc5e48bbe8cb6b0708fa2c12ea SHA-256: 5814cfbfdfa99aab8eca7923df5216299c468a267a07b8b3ea187934b16a9992
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. It contains numerous external URIs and links to compromised CMS uploads, suggesting it functions as a link farm to redirect users to potentially malicious sites. The PDF structure and embedded links are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://crysiq.ru/uplcv?utm_term=bigg+boss+kannada+season+8+live+streaming+free PDF link annotation
    • https://mgrenginiai.lt/ckfinder/userfiles/files/65056207157.pdfIn PDF document text
    • http://isisthailand.org/file_media/file_image/file/fojomipoj.pdfIn PDF document text
    • https://thailonghoang.vn/upload/files/vedim.pdfIn PDF document text
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/5cab86b6f0b36b21dbf35b6ed1a08542/zikagisatujid.pdfIn PDF document text
    • http://pphu-joanna.pl/fckpliki/file/704692325.pdfIn PDF document text
    • http://www.alex-vasilkov.ru/images/wisdom/file/1872834443.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613d3fc124f79---ganeli.pdfIn PDF document text
    • http://p-jtech.com/userData/board/file/73094497378.pdfIn PDF document text
    • http://reklamavysocina.cz/UserFiles/File/jekovu.pdfIn PDF document text
    • http://poney-club-romilly-aigre28.fr/userfiles/file/43801483906.pdfIn PDF document text
    • https://armagedonspedycja.pl/files/file/20664604407.pdfIn PDF document text
    • http://qianxi.cn/filespath/files/20210904043528.pdfIn PDF document text
    • http://superfasttv.com/uploads/files/zevoxedafawogejiguzifo.pdfIn PDF document text
    • http://deaprogettazioni.it/userfiles/files/nasisutomemupabibosobu.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/161343db137e3d---malurigawurarepiz.pdfIn PDF document text
    • http://bonsite.nl/phpcmsys/file/72485658598.pdfIn PDF document text
    • https://terracell.pt/images/file/gofipubuvusaxukujokataz.pdfIn PDF document text
    • https://icoachyou.biz/images/ckeditor/files/zilabiwotabanapawuzaju.pdfIn PDF document text
    • https://norservis.cz/files/files/tilegudevezagovuwegisev.pdfIn PDF document text
    • http://starroadchina.com/userfiles/file/34506424437.pdfIn PDF document text
    • https://hgb.se/filer/file/4774575330.pdfIn PDF document text
    • http://hemeringen.de/ckeditor_ablage/userfiles/files/tigozufazago.pdfIn PDF document text
    • http://hawaiianhunareiki.it/file/fomawalesib.pdfIn PDF document text
    • https://doellefjelde-mussemarked.dk/images/newsmail/file/14537034956.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_off0000d024.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD024 17168 bytes
SHA-256: a0a9344204c54d6d634145ac2a6cc101f4366e001342c92daf35dff8307880ca
font_01_sfnt_off0000fc91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC91 11256 bytes
SHA-256: 0785aa0818f48c97c22a5cf3f0d20117264b3affcd5a51158ad9aa23e833a751
font_02_sfnt_off000116da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1