Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c8a0b807d461a41…

MALICIOUS

PDF

79.2 KB Created: 2021-09-18 14:48:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: cdf060838a87faa50fccfdc8ea7f9b42 SHA-1: 4fb444259c9552ba3efc9730debc86a1a9d9fc73 SHA-256: 8c8a0b807d461a41e6f9bedc23b76cd4570c92e5b61c05bd7ef61db7f2fc532f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm or phishing lure. The ClamAV detection and ML classifier strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malware distribution or phishing campaigns, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://huntic.ru/uplcv?utm_term=aplikasi+edit+video+online+tanpa+watermark+pc PDF link annotation
    • http://orvositudasbazis.eu/images/upload/file/jenenivekuxuzet.pdfIn PDF document text
    • http://vkts.se/userfiles/file/leraxesuk.pdfIn PDF document text
    • https://susta.vn/userfiles/file/93787163788.pdfIn PDF document text
    • http://schubert-hh.de/image/file/wivumofomekidogefiv.pdfIn PDF document text
    • http://ticaproduce.com/ckfinder/userfiles/files/femitanozozaveme.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1613c7819992bc---batetim.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/f53d8255e1afaea21432e4f10d3f2fd4/73422131549.pdfIn PDF document text
    • http://tranindo.com/Uploads/userfiles/files/febidugeririmozoduxeva.pdfIn PDF document text
    • https://zifu-tech.com/app/webroot/userfiles/files/zujuruvizawuvoxanakiwok.pdfIn PDF document text
    • http://c2r.su/uploadfiles/file/2021091617311773499.pdfIn PDF document text
    • http://biafrapol.pl/pliki/file/95573456481.pdfIn PDF document text
    • http://homespakistan.net/magzine/uploadfiles/file/57044303789.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613ad66d634be---mugotomodowuwig.pdfIn PDF document text
    • http://zsdbiopharm.com/upload/files/44659583510.pdfIn PDF document text
    • http://jessie.vn/images/ckeditor/files/2056887950.pdfIn PDF document text
    • http://otohyundaidanang.com/uploads/image/files/libariduwipuropemag.pdfIn PDF document text
    • https://auto826.vnpec.xyz/uploads/files/kirojipafabafufazolexafed.pdfIn PDF document text
    • http://aaz.sk/editor_uploads/files/napawasuziroje.pdfIn PDF document text
    • http://nokianhakkablue.ru/ckfinder/userfiles/files/katuxaradizanum.pdfIn PDF document text
    • https://misbahelmudii.org/ckfinder/userfiles/files/93974685998.pdfIn PDF document text
    • http://dekoblickfang.de/userfiles/file/62182738917.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613f4de193afd---96531942584.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614236fe8ee71---54343485788.pdfIn PDF document text
    • http://airconbank.com/upload/fckeditor/file/87082233025.pdfIn PDF document text
    • http://korvet-sp.ru/userfiles/file/jagulumipusaxomosa.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_off0000d205.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD205 16924 bytes
SHA-256: 9d67d7a0693eda1ca8e547a484aca4475e2a749c7be626872fc763860d345389
font_01_sfnt_off0000fdd4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDD4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000115eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115EB 10900 bytes
SHA-256: 318f8fffb70105a97f7adcde1cf86c067442a5f8b76fcda819221a6792632c70