Malicious PDF — malware analysis report

Static analysis result for SHA-256 d721a4fb20926cf1…

MALICIOUS

PDF

76.3 KB Created: 2021-09-19 17:19:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c6005f11f10b158d71919f86c5489d24 SHA-1: f284c8b73e394393389aefe774b935aea1b31d7a SHA-256: d721a4fb20926cf1aaa9fb49ffa3b41c394ab53be6a566d5259ad0dc605bf067
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, many of which point to disposable domains and are structured as link farms, a common tactic for phishing or distributing further malware. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests this malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://equipociclistaugeraga.com/ciclistas/userfiles/file/tefolatabigerukodi.pdf In PDF document text
    • https://isabellepieman.com/userfiles/file/74318918876.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/161461bcc7d541---gufarufitite.pdfIn PDF document text
    • http://oa30us.com/userfiles/file/dosupore.pdfIn PDF document text
    • http://rem-stroymont.ru/img/file/pikivubimetitoseb.pdfIn PDF document text
    • http://e-menu.hu/editor_up/91723272798.pdfIn PDF document text
    • http://llux.vn/uploads/files/9734572581.pdfIn PDF document text
    • https://b2b-intelligence.it/uploads/file/jodasiganuwakatetuta.pdfIn PDF document text
    • https://alnahamgroup.com/userfiles/file/30804844665.pdfIn PDF document text
    • http://fsf-vastroad.com/userfiles/file/wawejare.pdfIn PDF document text
    • https://hidropomp2008.com/uploads/userfiles/file/26487725666.pdfIn PDF document text
    • https://nutricount.cz/UserFiles/File/wotejoxabir.pdfIn PDF document text
    • https://episcopiaoradiei.ro/files/5245996865.pdfIn PDF document text
    • http://offerparts.com/upload/files/84583320658.pdfIn PDF document text
    • http://a-swiss.com/upload/userfiles/file/5390262295.pdfIn PDF document text
    • http://artecgroupservices.com/imagenes/file/dusuzawe.pdfIn PDF document text
    • http://bettaletroom.com/file_media/file_image/file/sonejakabizifipotixetosa.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161332e4202993---tilagebujuzo.pdfIn PDF document text
    • https://cytokin.ca/upload/editor/file/lifevebowopefipot.pdfIn PDF document text
    • http://on-video.com/movies/movie_data/file/nubozogibatefad.pdfIn PDF document text
    • http://ristoranteyuri2.com/userfiles/file/54564572312.pdfIn PDF document text
    • http://lunaleo.pl/userfiles/file/vafufewukunitekozebike.pdfIn PDF document text
    • https://altaamir.ipixpms.com/Rapport/public/assets/ckfinder/userfiles/files/25007039522.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=call+history+any+number+premium+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_off0000c433.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC433 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dc45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC45 17888 bytes
SHA-256: 36a45e2d10bb90639df4ca9f8ac54508dfc948d5395b0aac4a8eea698b9ab07a
font_02_sfnt_off00010abc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10ABC 10992 bytes
SHA-256: 3e6eac40c141e79250d64656d1ae836f4709f0a2aaf4121f2ce8c0e7c68f1034