Malicious PDF — malware analysis report

Static analysis result for SHA-256 0f09cb3ad73edfc5…

MALICIOUS

PDF

81.1 KB Created: 2021-09-17 04:15:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 4858e0837c5baab705e94db67591dcfd SHA-1: 36ceecc724a3e99bdf59b443d0f19de68a2dcc96 SHA-256: 0f09cb3ad73edfc5d64af4a938540401734e152f6bdef84e4b5b6c89b4526bf1
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to other PDF files hosted on various domains, suggesting a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the nature of the embedded URLs and the heuristic firings point towards a malicious document designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://kvizek.hu/ckfinder/userfiles/files/88293046424.pdf In PDF document text
    • https://proxkimya.com/resimler/files/27230986119.pdfIn PDF document text
    • https://lotteppta.net/beta/assets/file/nenejizabejitefeg.pdfIn PDF document text
    • http://oticonshop.net/ckfinder/userfiles/files/31059594619.pdfIn PDF document text
    • https://zoomkish.com/basefile/zoomkishcom/files/vukavivon.pdfIn PDF document text
    • http://rebeccafantarchitetto.it/userfiles/files/sozovepelifijepuvibitaweb.pdfIn PDF document text
    • http://xinyuemu.net/assets/202109/files/20210917055551846217.pdfIn PDF document text
    • http://ranaghatpchsschool.org/userfiles/file/sazulukavegodarorizaxupiz.pdfIn PDF document text
    • https://cplastik.eu/data/cms/file/pakenifenulozukitozom.pdfIn PDF document text
    • https://www.cdsale.org.au/application/third_party/ckfinder/userfiles/files/sonafuwisopudewenuf.pdfIn PDF document text
    • http://devitohomesorlando.com/userfiles/files/lidejupazidarub.pdfIn PDF document text
    • https://fonixkoncert.hu/upload/file/14671789754.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613644efc0e5c---8979927512.pdfIn PDF document text
    • https://xn--49st2et51duvk.com/upload/files/28057883037.pdfIn PDF document text
    • http://csc025.com/userfiles/file/20210910005204_pof5ee.pdfIn PDF document text
    • http://restokrat.info/userfiles/file/1816409273.pdfIn PDF document text
    • http://xn--krmer-dnnebacke-1kb72b.de/files/file/toguvi.pdfIn PDF document text
    • http://fxlcd.com/upload/file/9047120096.pdfIn PDF document text
    • https://tabularasa.lv/sites/tabularasa/uploads/documents/files/fopadapovurabuzarusevelag.pdfIn PDF document text
    • http://wadirumshootingstars.com/userfiles/file///93538444077.pdfIn PDF document text
    • https://dovolena-jiznicechy.cz/uploads/72039689228.pdfIn PDF document text
    • http://www.koeru.eu/failid/file/9898709973.pdfIn PDF document text
    • http://hcstonetw.com/uploads/files/202109122229234729.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=track+2+nfc+apkPDF 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_off0000d628.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD628 9992 bytes
SHA-256: 1a23c18a6e400d96cb5901634d3e28ab2c6ca03bb203159ab56cff56c0b7dd86
font_01_sfnt_off0000ec79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC79 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001048b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1048B 19248 bytes
SHA-256: 2e2b2b22c1291f18b4a4c7191aaa1ea6e5fa54ece2fda7ce7372503e5f274ace