Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5e3aabfe85a7780…

MALICIOUS

PDF

89.6 KB Created: 2021-09-09 10:43:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ab678582f071d2cffb72166e63c2c3c7 SHA-1: 12a8f81a59dd67ae2ee8e5852db32eec720caed2 SHA-256: c5e3aabfe85a778083a833d538ebc5532df4ca202b16e04e12f08c2689c7d59b
126 Risk Score

Malware Insights

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

The file was detected by ClamAV as Pdf.Phishing.Trojan and an ML classifier flagged it with high confidence. Heuristics indicate it functions as a link farm, directing users to numerous other PDF files hosted on distinct domains. The presence of multiple external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly suggest a malicious intent to manipulate search engine results or distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

Heuristics 5

  • 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.
  • 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://whereestar.com/marinarubicon/admin/file/54974602688.pdf In PDF document text
    • https://dispecom.com/cms_dispecom/sgi_userfiles/userfiles/files/97845212323.pdfIn PDF document text
    • http://miwon.com.vn/app/webroot/uploads/files/rigotasidaruro.pdfIn PDF document text
    • http://mevlanaasm.com/resimler/files/rexuzokeketum.pdfIn PDF document text
    • https://pfollowers.com/ci/userfiles/files/samipekuweve.pdfIn PDF document text
    • https://eurochen.com/UpFiles/WebEditorFiles/file/1753341517.pdfIn PDF document text
    • https://amursvoidom.ru/media/files/81100665642.pdfIn PDF document text
    • http://dekogard.net/deko/veri/_files/48951863972.pdfIn PDF document text
    • https://chrmglobal.com/userfiles/file/6276893512.pdfIn PDF document text
    • https://ekransamara.ru/files/siporogozevakovusigom.pdfIn PDF document text
    • http://zeguvietnam.com/uploads/ckfinder/files/miwumiv.pdfIn PDF document text
    • https://vgi-vn.vn/app/webroot/img/files/5811604276.pdfIn PDF document text
    • http://jmlukanich.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/bulazut.pdfIn PDF document text
    • http://picassogift.com/Uploadfiles/files/1375623139.pdfIn PDF document text
    • http://kabaretyimpresariat.pl/Upload/file/24810277335.pdfIn PDF document text
    • http://www.yoko-ono.be/images/userfiles/file/41228090239.pdfIn PDF document text
    • http://coachhouse.info/assets/file/53665539811.pdfIn PDF document text
    • https://amzentransportationindustries.com/admin/imagetemp1/file/10652053891.pdfIn PDF document text
    • http://print-resource.co.uk/ckfinder/userfiles/files/30715448241.pdfIn PDF document text
    • http://lawngo.net/fckfiles/86295833659.pdfIn PDF document text
    • https://altsovmun.ru/userfiles/file/5145792788.pdfIn PDF document text
    • https://balajihighfields.in/userfiles/file/9034289560.pdfIn PDF document text
    • http://pravkniga.ru/files/userfiles/files/fasagavebawokamiropexewu.pdfIn PDF document text
    • https://casabresciani.it/uploads/file/giwivozu.pdfIn PDF document text
    • http://aibasylhet.edu.bd/app/webroot/ckfinder/userfiles/files/suzokenarosi.pdfIn PDF document text
    • http://childprotectionindia.com/lexcyberia/userfiles/files/pebisorodanezexebimide.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=nes+roms+free+download+for+androidPDF 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_off0000f95e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF95E 18328 bytes
SHA-256: 3065b8baef9bc9a5d5f21ff5840c83ce3711e82a82cd312831dc97b0630b8bb0
font_01_sfnt_off000128ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128AC 10480 bytes
SHA-256: aa03157355c585170d0b695637afa9a91bb3de010b022c659edadb48b0bdf497
font_02_sfnt_off0001407f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1407F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1