Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8bcf8684863632b…

MALICIOUS

PDF

70.6 KB Created: 2021-09-16 05:46:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 265e3f15af5af0289056cf58e6fc379a SHA-1: f8190f915b118c0575594f9baf81dd370c21d878 SHA-256: c8bcf8684863632bfb12904aa77bc0327c128b4bd17a2792e0d277988a7c0b47
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, many pointing to potentially malicious domains, and is flagged by ClamAV as a phishing trojan. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a deliberate attempt to create a link farm, likely to distribute malicious files or redirect users to phishing sites. While no scripts were explicitly extracted, the nature of the PDF and its embedded links suggests an attempt to trick users into downloading further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://mbfeed.vn/upload/files/deriwakeliribabapenejoxo.pdf In PDF document text
    • https://santevita-bg.com/ckfinder/userfiles/files/2633782472.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16133a9b4826c9---78631518525.pdfIn PDF document text
    • http://mclarenquartz.in/ci/userfiles/files/69524863684.pdfIn PDF document text
    • https://perfecthospitals.com/ckfinder/userfiles/files/lobef.pdfIn PDF document text
    • https://congchung7.com/upload/file/varolakaketutebanubod.pdfIn PDF document text
    • http://hcstonetw.com/uploads/files/202109051238426908.pdfIn PDF document text
    • http://xn--80ab1a9a.xn--p1ai/sadm_files/95222774522.pdfIn PDF document text
    • https://saglamahsapkutu.com/img/editor/image/file/rukixenu.pdfIn PDF document text
    • http://www.yevres.fr/ckfinder/userfiles/files/16852065049.pdfIn PDF document text
    • http://novosib-sport.ru/ckfinder/userfiles/files/puxinesepopujefik.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/b40842570770c2e927ec761fcfc668f9/5907835732.pdfIn PDF document text
    • https://aarhuskortet.dk/images/file/71997652489.pdfIn PDF document text
    • http://sprinter-lab.ru/content/File/gemaliri.pdfIn PDF document text
    • http://synthecinter.com/userfiles/files/40460636476.pdfIn PDF document text
    • http://oris-am.com/editor_up/32534038330.pdfIn PDF document text
    • http://caminodesantiagoenmoto.com/assets/ckfinder/core/connector/php/uploads/files/dirugiro.pdfIn PDF document text
    • http://rungruangsteel.com/public/upload/userfiles/files/87760604084.pdfIn PDF document text
    • http://mylodge-naoshima.com/88273536804.pdfIn PDF document text
    • http://thomasgearon.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/76545561755.pdfIn PDF document text
    • https://tepatsasaran.com/contents/files/joxuzugoxevirakosipa.pdfIn PDF document text
    • https://www.studioline.ie/ckfinder/userfiles/files/92496560194.pdfIn PDF document text
    • http://shamayachts.com/upload/file/96962256385.pdfIn PDF document text
    • http://www.pzkexie.com/up_files/file/maluwavipap.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=hobbs+and+shaw+free+downloadPDF 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_off0000b3c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3C8 16132 bytes
SHA-256: 7af0b041c2f3b81b3157688e47c783359866251dad2c5615193d931bd0bc9de9
font_01_sfnt_off0000dd13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD13 10476 bytes
SHA-256: 83c76995f7be191d6fd34e5511f5cb994740c6814044a148e921ce468cb43a28
font_02_sfnt_off0000f4d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1