Malicious PDF — malware analysis report

Static analysis result for SHA-256 1039c48b4f62532c…

MALICIOUS

PDF

72.2 KB Created: 2021-09-16 05:05:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 809fde9c1380e3319f8846d604b61ef5 SHA-1: bb4d74b4d7a4303a1470318ab94ce7f7aa70cd32 SHA-256: 1039c48b4f62532c12aee1a2c690bff3b4cd403ddba4ff24840eb874765282fe
126 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous external URIs, with one specifically pointing to a 'wifi sniffer apk free download for android' lure, suggesting a social engineering tactic to trick users into downloading malware. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further confirms the malicious intent by identifying the document as a link farm hosted on disposable domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9915

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://wastran.ru/uplcv?utm_term=wifi+sniffer+apk+free+download+for+android PDF link annotation
    • http://tochalco.com/uploads/files/91689434730.pdfIn PDF document text
    • http://siciny.pl/userfiles/file/xazetax.pdfIn PDF document text
    • http://uro-medical.pl/zdjecia/fotki/file/fatox.pdfIn PDF document text
    • https://fnb-concepts.com/images/uploads/files/64384407658.pdfIn PDF document text
    • http://kelt.pl/userfiles/file/dumil.pdfIn PDF document text
    • http://ilsungwarehouse.com/userData/ebizro_board/file/juxeguzisenoperesifow.pdfIn PDF document text
    • http://focalthai.com/file_media/file_image/file/saxibovujipafadaz.pdfIn PDF document text
    • https://keyseries.us/userfiles/file/pokapurapadelo.pdfIn PDF document text
    • http://mimarathi.live/assets/ckfinder/core/connector/php/uploads/files/37916911068.pdfIn PDF document text
    • http://denge.aero/upload/files/garip.pdfIn PDF document text
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f90b39569f---gufopupimezade.pdfIn PDF document text
    • http://tns-china.cn/editor_upload_image/file/28971453717.pdfIn PDF document text
    • http://colorsoftexas.com/ckfinder/userfiles/uploads/darebudeduwut.pdfIn PDF document text
    • http://hanlacsclub.com/ckupload/files/20653308217.pdfIn PDF document text
    • http://ulv-fogger.ru/d/files/11316115429.pdfIn PDF document text
    • https://gancza-yacht.pl/userfiles/file/26928885062.pdfIn PDF document text
    • http://crescentcarpets.com/userfiles/file/53217954471.pdfIn PDF document text
    • http://leadingedgecorporate.com/user_images/file/9999155323.pdfIn PDF document text
    • https://igk-lilienthal.de/downloads/wezufezifu.pdfIn PDF document text
    • http://xn--b1agpbmdtf.xn--p1ai/upload/file/rojixa.pdfIn PDF document text
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/ffqf1dpnpirr3kgd555kqi2vk0/83087422956.pdfIn PDF document text
    • http://osmed.cz/app/webroot/files/files/53774714544.pdfIn PDF document text
    • http://kiko168.com/UploadFile/file/20210914042857619.pdfIn PDF document text
    • http://poexali.org/static/image/_u/system/files/72017003611.pdfIn PDF document text
    • http://studio-orlandini.com/userfiles/files/lipofuxaguxul.pdfIn PDF document text
    • http://dobrasekacka.cz/userfiles/file/36714242697.pdfIn PDF document text
    • 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_off0000b8f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8F8 16376 bytes
SHA-256: 916319e7c679bee5d13ae3877d31742e1120e6f53bf29bec5a759443b37caff0
font_01_sfnt_off0000e27b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE27B 10564 bytes
SHA-256: e4a40bfe0ecef209b3fc6c28bc25a648223313d5fde41835ddcd1b7a4a2bc74c
font_02_sfnt_off0000fab9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAB9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1