Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8e0371e632cedfb…

MALICIOUS

PDF

84.3 KB Created: 2021-09-11 15:58:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 2c1aaac8f736d2c98016fb219d308b79 SHA-1: d0e3a85c43d64557c5f0c18b8bbb867fce4a68f8 SHA-256: a8e0371e632cedfb961d6792a5661bcc9fe73036685359d64aa4a9af39922102
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 presence of numerous embedded URLs, many pointing to disposable domains and configured as a link farm, strongly suggests a phishing or malware distribution scheme. The document body is heavily obfuscated and unreadable, further supporting the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 https://dnmpaint.com/sdcc/images/file/siperoramemivonu.pdf In PDF document text
    • http://thinhhoanggia.vn/Images_upload/files/86504161384.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/161396a5a802a7---xofapibazamozu.pdfIn PDF document text
    • https://avukatwebsitesi.trakyasoft.com/upload/files/97096608622.pdfIn PDF document text
    • http://nyitotthetvege.kastelyszallodak.hu/userfiles/files/zidilopet.pdfIn PDF document text
    • http://marthomaiticherukole.com/userfiles/file/30200584541.pdfIn PDF document text
    • http://zartmobilia.com/userfiles/file/20210908223252.pdfIn PDF document text
    • http://dongamold.com/fckeditor/upload_files/file/11635980029.pdfIn PDF document text
    • https://rmp-familienanzeigen.de/cms/files/lulitivosukakomubixedese.pdfIn PDF document text
    • http://simsvizag.com/contentimages/file/roxosujevubexinerowononog.pdfIn PDF document text
    • http://aotwresort.net/ckfinder/userfiles/files/gefejorifosenobowul.pdfIn PDF document text
    • http://levne-pohary.cz/UserFiles/File/wetizaxiwexurovobun.pdfIn PDF document text
    • https://snf.styleguides.ch/userfiles/files/24746554700.pdfIn PDF document text
    • https://shidoremicrosys.com/media/lisexa.pdfIn PDF document text
    • http://medtravel.lv/images/hand_uploaded/files/wexojageroponu.pdfIn PDF document text
    • http://magogaralbamoble.com/galeria/files/feramumavunitobirukuni.pdfIn PDF document text
    • https://ural-aiti.ru/admin/ckfinder/userfiles/files/jigazofodelo.pdfIn PDF document text
    • http://spreewaldatelier.de/img/editor/file/vovokawuguminegelizoxin.pdfIn PDF document text
    • https://needletherapy.eu/upload/file/vezixutaxowasoxal.pdfIn PDF document text
    • http://changwontour.kr/FileData/ckfinder/files/20210905_4840F181797A4E5A.pdfIn PDF document text
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bdb7a54225---25539673053.pdfIn PDF document text
    • http://sartor.ru/upload/files/62070364823.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=my+life+as+a+zucchini+streamingPDF 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_off0000db4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB4D 10928 bytes
SHA-256: 7da38f09fd9f3da98d56cc468b7e61f6a6499ac1ff82fa7912469db104dac5a7
font_01_sfnt_off0000f47f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF47F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010c91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C91 21124 bytes
SHA-256: 176363bd3a6c5c72d6a3c0be308af4dac7df5a45c7596d7f099a991df488eea7