Malicious PDF — malware analysis report

Static analysis result for SHA-256 981e137658a579a3…

MALICIOUS

PDF

69.4 KB Created: 2021-09-27 22:14:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 12b2814fb2928635f29613ff79431f18 SHA-1: 1751ef519c54653d5966e20584913aab8e9835d1 SHA-256: 981e137658a579a33f6def29c1382b4678bf5681e66feb81951afdae974e36d1
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan' and an ML classifier indicating maliciousness. The document contains numerous embedded URLs pointing to external PDF files, suggesting it functions as a link farm designed to redirect users to potentially malicious sites. The presence of external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic further support this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://chcial.ru/uplcv?utm_term=positive+adjectives+beginning+with+b
    • https://mavibusiness.it/file/62180088725.pdf
    • http://taaltoetsvo.nl/userfiles/file/18520164607.pdf
    • http://liily.jp/upload/file/20210911225713.pdf
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/51b04a8ba478f96fa49e0e73fa07192a/xiwukegejo.pdf
    • http://oppedisanorobertosrl.com/userfiles/files/27247909078.pdf
    • https://hopadive.cz/ckfinder/userfiles/files/21476546704.pdf
    • http://namkhoabacninh.com/images/files/jiteso.pdf
    • http://nineslash.com/user_file/file/nezidod.pdf
    • http://nebovsem.ru/app/webroot/files/files/silovi.pdf
    • http://hanasushichoice.com/uploads/files/37268478005.pdf
    • http://thuonghieutoancau.vn/uploads/files/23412008808.pdf
    • https://panificioilcavaliere.it/userfiles/files/pigifulu.pdf
    • http://wordtmann.beckbauer.eu/ckfinder/userfiles/files/33321220395.pdf
    • http://opgzvh.hr/upload/file/92749966624.pdf
    • http://hongpakthai.com/ckfinder/userfiles/files/19813134544.pdf
    • https://aldwalia.com/userfiles/files/lenozeloxod.pdf
    • http://myblindz.com/fck_user_files/file/suxin.pdf
    • http://maxbrio.kr/files/files/97418052749.pdf
    • http://www.jfac.kr/ckfinder/userfiles/files/95585635729.pdf
    • http://miet-boot.ch/images/uploadedimages/file/buvojuloxobofemiw.pdf
    • http://workontext.ru/media/file/xaladimanediv.pdf
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b1a329d136---tekudesuvusunawizi.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000adfa.bin
b6cf28d70eefce33586a954ca3e76a0df9eb6e86dde1cd5d27592873277dda9c		 pdf-font-stream PDF embedded font (sfnt) at offset 0xADFA 16216 bytes
font_01_sfnt_off0000d6e3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1		 pdf-font-stream PDF embedded font (sfnt) at offset 0xD6E3 16792 bytes
font_02_sfnt_off0000eefa.bin
9039c610751cfc5ceb307013e54b2f3ce5a0a28599ca9e71db15a5662098ce66		 pdf-font-stream PDF embedded font (sfnt) at offset 0xEEFA 10928 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.