Malicious PDF — malware analysis report

Static analysis result for SHA-256 77cb916232194ab8…

MALICIOUS

PDF

89.5 KB Created: 2021-09-19 09:43:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 4e126230e10a4bed4ed452bc5fd6fd74 SHA-1: 8062a170de5cc2364192ae68f0daec525a898fe3 SHA-256: 77cb916232194ab8b111b3966c7f6a1def71cb312e7dae1d55301a2eb93c3d61
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document contains numerous links to disposable hosting, suggesting a tactic to distribute malicious content or phish for credentials. The embedded URLs, while numerous, do not appear to directly execute code but rather redirect to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

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 http://kenzoum.org/home/integrity/public_html/ckfinder/userfiles/files/21908457311.pdf In PDF document text
    • http://npas.ru/pic/file/42371718043.pdfIn PDF document text
    • https://broadcasthub.com/ci/userfiles/files/70281526917.pdfIn PDF document text
    • http://c2r-auto.com/uploadfiles/file/2021091702435173499.pdfIn PDF document text
    • http://elmbbq.com/uploads/files/23034809619.pdfIn PDF document text
    • https://hoangmailogistics.com/asset/site/files/90695816022.pdfIn PDF document text
    • http://760_709737661.mildmedia-dev.eu/uploads/userfiles/files/guvedasuzot.pdfIn PDF document text
    • http://quangcaosmsgiare.com/media/ftp/file/87381623453.pdfIn PDF document text
    • https://oilbasaro.com/web/images/ckfinder/files/20210913013319.pdfIn PDF document text
    • https://sierrainstruments.cn/fckeditor/editor/filemanager/connectors/php/fckeditor/upload/202109/file/4766709988.pdfIn PDF document text
    • http://bjsixiang.com/jingkelun/userfiles/files/20210906140811.pdfIn PDF document text
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/b2d1556f4d934cfca19b3d0e8cf3955a/58114328356.pdfIn PDF document text
    • http://kite-surf.sk/files/xugawexodimawovil.pdfIn PDF document text
    • https://hoatuoi360.vn/uploads/files/71294418489.pdfIn PDF document text
    • http://www.childofafrica.org/media/userfiles/file/joritududeborubil.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614436a4e0333---vamaxovujuxumilepavobu.pdfIn PDF document text
    • http://vividconcept.in/userfiles/file/katuvelezis.pdfIn PDF document text
    • http://festacreativita.org/userfiles/file/57064501648.pdfIn PDF document text
    • https://ganport.pl/userfiles/file/vejinugilanesupebabe.pdfIn PDF document text
    • http://studioprogettoarchitettura.eu/userfiles/files/68580926900.pdfIn PDF document text
    • http://klpa.net/userData/board/file/61878925360.pdfIn PDF document text
    • http://studioprogettoarchitettura.eu/userfiles/files/24675712595.pdfIn PDF document text
    • https://podiummagazinenews.com/ckfinder/userfiles/files/mupupunuzuk.pdfIn PDF document text
    • http://elijasprojekts.lv/files/file/35441760787.pdfIn PDF document text
    • https://lrsdev.com/userfiles/file/94898137036.pdfIn PDF document text
    • http://logicamail.it/draft/media/26000365647.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=vidmate+new+version+2021+apk+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_off0000f977.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF977 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011189.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11189 17192 bytes
SHA-256: 3a6ee6668b75feddd388d4b902e7fa09ca4c88422c9e16bf843e9fa9ee0171cf
font_02_sfnt_off00013e51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E51 11060 bytes
SHA-256: 86d7401ade69da31f06948fb23b67dfc73301bdf5aa9823d94d60f9523818972