Malicious PDF — malware analysis report

Static analysis result for SHA-256 c6b9141fff3bc5a0…

MALICIOUS

PDF

70.9 KB Created: 2021-09-28 07:28:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 9fd264737f00d6c05ae31a2b122f6e4c SHA-1: 8c05ada08ac86afcdab8b5db7c5b6668043a7c16 SHA-256: c6b9141fff3bc5a0e97bb7317827745b9fd6dd0a6ae89182d0c18e8976aa5e8f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to disposable hosting, suggesting a link farm or phishing lure. The PDF structure and embedded URLs are consistent with attempts to redirect users to malicious sites, potentially for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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=present+continuous+tense+exercises+worksheets PDF link annotation
    • http://alnadaoil.com/userfiles/file/9915386204.pdfIn PDF document text
    • http://seed-hongkong.com/uploads/file/jesuzemitomelog.pdfIn PDF document text
    • http://good163.cn/Uploadfiles/files/65743080303.pdfIn PDF document text
    • https://hometutorsdelhi.com/userfiles/files/kevozag.pdfIn PDF document text
    • https://ijacr.net/assets_admin/ckfinder/core/connector/php/uploads/files/36552905155.pdfIn PDF document text
    • https://geneticapanama.com/userfiles/file/lujumigu.pdfIn PDF document text
    • http://veterina-hrib.cz/user-uploads/files/xiwuwiwuxol.pdfIn PDF document text
    • http://daiichibus.vn/uploads/news_file/73116312191.pdfIn PDF document text
    • http://parzenica-bialka.pl/userfiles/files/53259968660.pdfIn PDF document text
    • http://ipceurope.be/assets/file/97588193396.pdfIn PDF document text
    • https://nieruchomosciprzetargi.pl/files/file/veniwefarafofudoveluder.pdfIn PDF document text
    • http://exhibitionchannel.com/upload/gebeju.pdfIn PDF document text
    • http://badischer-kunstverein.de/ckfinder/userfiles/files/seluvok.pdfIn PDF document text
    • http://videocycling.info/files/file/1987558897.pdfIn PDF document text
    • http://www.enfersalus.com/ckfinder/userfiles/files/26881324316.pdfIn PDF document text
    • http://klick-tipp.info/ckfinder/userfiles/publics/files/davavimuxumuvi.pdfIn PDF document text
    • https://andrejc.si/files/file/1969175185.pdfIn PDF document text
    • https://icoachyou.biz/images/ckeditor/files/26984801325.pdfIn PDF document text
    • http://matonaklawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nolisujoxog.pdfIn PDF document text
    • http://www.alex-vasilkov.ru/images/wisdom/file/bijojolawalofefegalulosuw.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614475d91ffb6---wanebekazezo.pdfIn PDF document text
    • http://ardeche.proximeo.com/ckfinder/userfiles/files/55637136838.pdfIn PDF document text
    • https://thingstodobahrain.net/ckfinder/userfiles/files/lalotiresifezi.pdfIn PDF document text
    • http://nage-z.com/ckfinder/userfiles/files/xelifibadogeduzo.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_off0000b30e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB30E 16632 bytes
SHA-256: b335d6b65e6effae4a7f4ca431e5aadbad93e5938c93212919c63d3533084439
font_01_sfnt_off0000dd6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD6E 10500 bytes
SHA-256: 96429cf163e58b19234ce97f199abe1f782b1f35e66760c474cdc3ed6b4e7fa2
font_02_sfnt_off0000f562.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF562 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1