Malicious PDF — malware analysis report

Static analysis result for SHA-256 21456278daee334f…

MALICIOUS

PDF

69.8 KB Created: 2021-10-03 05:24:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 67aa130c83956d1ecf01979e58785817 SHA-1: 43566561705a417e09846e7c5aa848cb53386cb7 SHA-256: 21456278daee334f0963f20e279281905e7b86fc64c5b4cb0147540b7a93fb79
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded URLs, many of which point to external sites that host other PDF files. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicates a pattern of link farming on disposable hosting, suggesting a malicious intent to obscure the true destination or distribute content. The ML classifier and ClamAV detection strongly indicate maliciousness, likely related to phishing or malware delivery via these linked documents.

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://livstyle.ro/home/livstyle/public_html/uploads/files/wukasiguguneralap.pdf In PDF document text
    • https://fpcofmacon.com/nbloom/fckuploads/file/94481259579.pdfIn PDF document text
    • https://pamukoglu.com/userfiles/file/97559011699.pdfIn PDF document text
    • https://daaeportrett.no/upload/file/41038376634.pdfIn PDF document text
    • http://cukorbetegshop.hu/files/71527495545.pdfIn PDF document text
    • http://bassonconsulting.mc/userfiles/file/79466754690.pdfIn PDF document text
    • http://tjsijiqing.com/ckfinder/userfiles/files/2021/0913/5834638e34b81d0eba4d723fe1cc0bb3.pdfIn PDF document text
    • http://djpress.pl/Image/files/83036762828.pdfIn PDF document text
    • https://egyptsuntours.com/userfiles/files/mukikosa.pdfIn PDF document text
    • https://rougezenekar.hu/files/file/zizoduvifezinig.pdfIn PDF document text
    • http://breakevenpoint.pl/uploads/editor/file/lumaruzijoginasa.pdfIn PDF document text
    • http://xn--h1aaebajlcgx.xn--p1ai/sadm_files/25318015361.pdfIn PDF document text
    • https://manhalhealing.com/userfiles/file/mutelusawunenunaxasedip.pdfIn PDF document text
    • http://qishuochem.com/siicea/userfiles/file/migoxefezumatemin.pdfIn PDF document text
    • http://www.domplit2006.ru/ckfinder/userfiles/files/36573215908.pdfIn PDF document text
    • https://www.leadercaravans.com.au/application/third_party/ckfinder/userfiles/files/pimomamigatogesogi.pdfIn PDF document text
    • http://remont-elektro.eu/archiv/file/zifugufomumilavew.pdfIn PDF document text
    • http://phongthuyphatloc.com/luutru/files/61164712520.pdfIn PDF document text
    • http://sun-apartments.pl/data/pages/71694297130.pdfIn PDF document text
    • http://mimarkamilozkartal.com/userfiles/files/zosotarovafego.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131f55b0892b---notolu.pdfIn PDF document text
    • http://krishikhabar.net/assets/ckfinder/core/connector/php/uploads/files/84771715006.pdfIn PDF document text
    • http://cga82.com/admin/File/logonagen.pdfIn PDF document text
    • http://firmykominkowe.pl/Obrazki/edytor/file/9580520693.pdfIn PDF document text
    • https://www.ocnistudio.cz/ckfinder/userfiles/files/vunodedusafuwesodifez.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=for+and+on+behalf+of+letterPDF 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_off0000b40a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB40A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cc1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC1C 15044 bytes
SHA-256: 9b8027d549b9ff91e67c0e21d90b9d125080ca46c3eb0586b3d0a710314a71ae
font_02_sfnt_off0000f21f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF21F 10308 bytes
SHA-256: e6b2e98864285eafbc01da33e8c3aef205fdb0be89af90d50d40b29b3122b1a0