Malicious PDF — malware analysis report

Static analysis result for SHA-256 bd23785d167880a7…

MALICIOUS

PDF

82.0 KB Created: 2021-09-16 23:36:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 0fbb64bfef8a49e7b6d7d5b94099deee SHA-1: f223e87ed7a7a2894dc5401d30bf53354ae6c0cc SHA-256: bd23785d167880a7bccfa0078005360ab82b5d6e9880532c4c97fe47cfd49acd
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 suspicious domains and appear to be part of a link farm. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for link aggregation, suggesting a phishing or SEO spam campaign. No scripts were extracted, but the overall structure and URL distribution point towards a malicious intent to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://sjar-tech.com/uploadfile/file///2021091416582628.pdf In PDF document text
    • https://sharmtocairo.com/userfiles/files/piranatojerorolorewugete.pdfIn PDF document text
    • http://cesurmakina.com/userfiles/file/wovanuzebalo.pdfIn PDF document text
    • http://www.pacautomarketing.com/file/xofudepumazepive.pdfIn PDF document text
    • http://sdv.sk/userfiles/articles/file/85004431721.pdfIn PDF document text
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16133d038372e7---fokexemugejasesilajaleg.pdfIn PDF document text
    • http://dental-forum.ru/userfiles/file/69641977124.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16139d227f0a19---nuzaf.pdfIn PDF document text
    • https://wroclawmodelshow.pl/ckfinder/userfiles/files/73072428435.pdfIn PDF document text
    • http://fairbank-ia.org/admin/ckfinder/userfiles/files/6871182973.pdfIn PDF document text
    • https://lufty.cz/UserFiles/files/lezodizexajudufoninaz.pdfIn PDF document text
    • http://ncteonline.com/userfiles/file/16213527741.pdfIn PDF document text
    • https://tumujerrusa.com/userfiles/rivine.pdfIn PDF document text
    • http://salondebellezaanamariaromero.es/ckfinder/userfiles/files/migufemitoxixuzax.pdfIn PDF document text
    • https://mokshadhamnepal.org/userfiles/files/jiwasigekovisegububos.pdfIn PDF document text
    • http://angelofthewinds.net/ckfinder/userfiles/files/zekunimuwatinugivo.pdfIn PDF document text
    • http://italianopizzeria-pg.com/uploads/files/jekodi.pdfIn PDF document text
    • http://www.enjoyvaltellina.it/admin/ckfinder/userfiles/files/8088408317.pdfIn PDF document text
    • http://old.bgk-meshkova.com/ckeditor/ckfinder/userfiles/files/vogejunom.pdfIn PDF document text
    • http://wish-pharma.com/upload/files/wexamorub.pdfIn PDF document text
    • http://playbabydoll.com/userfiles/file/36810312021.pdfIn PDF document text
    • http://reliancefla.com/admin/images/file/fifur.pdfIn PDF document text
    • http://newcityhk.com/userfiles/87152493383.pdfIn PDF document text
    • http://otestmanager.com/club/data/userfiles/file/20210907024519.pdfIn PDF document text
    • http://turnwealthy.com/ckfinder/userfiles/files/fenegogiwilomut.pdfIn PDF document text
    • http://waycreon.net/bhaskar/yii/upload/files/refupezobalawirisi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=what+can+you+do+with+scaffolding+in+minecraftPDF 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_off0000dac5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAC5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f2dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2DC 11216 bytes
SHA-256: 02657e260f1f76dc43c861c40a157f523a12a462afe832c13aa1602e1d6b2503
font_02_sfnt_off00010cd3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CD3 17332 bytes
SHA-256: 889016c21639f920911d275a3d353d19753972e504b815b51efdbb3cdac93aab