Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b181639cbf313e2…

MALICIOUS

PDF

81.5 KB Created: 2021-09-17 21:22:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 475df82b599bd9d9dac8d572fa39ff4c SHA-1: a1aefb84a0f08bb201fe625dab4f8f7134e61855 SHA-256: 8b181639cbf313e22ee80549fd8338229bfffd7c0703bc529e57dd83cb47afb8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple compromised or unknown domains, some hosted on disposable infrastructure. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM rules strongly suggests a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://argol-editions.fr/userfiles/file/48168065094.pdf In PDF document text
    • https://bulendengin.com/upload/ckfinder/files/90136288845.pdfIn PDF document text
    • https://sluganarodu.org/userfiles/files/45786147198.pdfIn PDF document text
    • https://curtain.jinware.com/upload/files/40091298930.pdfIn PDF document text
    • https://www.vconsole.com/ckfinder/files/43967994431.pdfIn PDF document text
    • http://philipsphotographystudio.com/ranimusixosaxis.pdfIn PDF document text
    • https://llbyggodesign.se/UserFiles/files/selokuwewaxiled.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/6bf81e3432b0f97783e4a69db8896805/48107545339.pdfIn PDF document text
    • http://foto-klub.dk/userfiles/file/54029371600.pdfIn PDF document text
    • http://alvit-bk.ru/userfiles/file/39740648418.pdfIn PDF document text
    • https://pima-alarms.net/slicice/file/86501310742.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1614436e16f032---tigilo.pdfIn PDF document text
    • https://haltia.mx/sii/ckfinder/userfiles/files/61921390433.pdfIn PDF document text
    • http://dolonchem.com/upload/files/kawigosal.pdfIn PDF document text
    • https://adurucui.com/ckfinder/files/wozusira.pdfIn PDF document text
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/58ab0279efcbf010263684f586f4f604/xiruri.pdfIn PDF document text
    • http://technoprofile.ru/userfiles/file/wokalorawu.pdfIn PDF document text
    • https://xrtradingfeedback.com/cmsimages/file/66348563417.pdfIn PDF document text
    • http://topflexsports.com/uploads/govowuzufukapoz.pdfIn PDF document text
    • https://devcons.org/uploads/userfiles/files/36693993313.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=minecraft+house+small+ideasPDF 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_off0000dbf0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBF0 10836 bytes
SHA-256: 9265aaaeaaf190a9eba07e5e545f89cb20c47ff0911b59743f8b26015dc111ea
font_01_sfnt_off0000f4c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4C0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010cd2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CD2 17164 bytes
SHA-256: 6dbcd0c980982e2f1e7b1a7e340d54f32cdac620f2351483202c4ef50b9cb088