Malicious PDF — malware analysis report

Static analysis result for SHA-256 88fcc821f90a3d3a…

MALICIOUS

PDF

99.2 KB Created: 2021-09-13 17:44:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 467c1ffc3121e6f66f8109d45da2d2d1 SHA-1: 595da5afb2f1b7d794f43eb78c7a84a4c7ff3e99 SHA-256: 88fcc821f90a3d3a201b6ae7ab2c7bbda3f62e3bedddbf0b078749f6241b9f88
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the numerous extracted URLs suggest the document functions as a link farm, directing users to potentially harmful sites. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the technical indicators.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9875

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://ruihuitax.com/files/file/419208585.pdf In PDF document text
    • http://www.psoealora.es/ckfinder/userfiles/files/92786969950.pdfIn PDF document text
    • http://denis-lefebvre-services.com/fichiers/file/10566754162.pdfIn PDF document text
    • http://nage-z.com/ckfinder/userfiles/files/69257199984.pdfIn PDF document text
    • http://tienphat.vn/imagesflashupload/file/gudatudesalonadobaxaxupo.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/5444851521.pdfIn PDF document text
    • https://myphambambi.com/webroot/img/files/junotusavujuwiruresumut.pdfIn PDF document text
    • http://reclameindex.nl/images/uploads/39433472336.pdfIn PDF document text
    • https://didaktika.drmix.cz/uploads/files/93858852936.pdfIn PDF document text
    • http://kdwatch.net/upload/files/2021091109473693.pdfIn PDF document text
    • http://leoclubmarsala.it/userfiles/files/96976060430.pdfIn PDF document text
    • http://mirai-kankyo.com/userfiles/files/61460980155.pdfIn PDF document text
    • https://sealand-pptc.com/userfiles/file/96531592465.pdfIn PDF document text
    • http://dichvuhieuchuan.com/upload/files/poxekovizego.pdfIn PDF document text
    • http://richmediahouse.com/admin/uploads/file/bewuvebigixipazinaneb.pdfIn PDF document text
    • https://kolkataangikar.org/ckfinder/userfiles/files/naxonasipovoromibeleroxon.pdfIn PDF document text
    • http://kaies.cn/upfiles/210911010113171870u74cn3.pdfIn PDF document text
    • http://clearspace-design.com/CKEdit/upload/files/jadiguwuwijixew.pdfIn PDF document text
    • http://stopguepes72.fr/userfiles/file/32164226989.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/vonifulofalezufotis.pdfIn PDF document text
    • http://automotiveenergy.cz/userfiles/file/93852049065.pdfIn PDF document text
    • http://baoveantam.info/upload/files/penexazodenegobaz.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130cc7a182c4---29853707151.pdfIn PDF document text
    • http://rigosarchitects.gr/userfiles/file/73276591451.pdfIn PDF document text
    • http://gtlfuelmarine.com/userfiles/file/53931447355.pdfIn PDF document text
    • https://digireg.pl/upload/dukotuzuradijolejovuko.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=how+do+i+install+kodi+on+my+android+boxPDF 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_off00011d8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D8C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000135a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135A3 10804 bytes
SHA-256: 45f504e8ace825849592ee592a0eb4ec1aabb6758b732d03383943e10dc35236
font_02_sfnt_off00014e83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14E83 18380 bytes
SHA-256: f753873ee6d60fc357d72f37c6244b15e5ca31005cff58e3483b9b4449666f6b