Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b9ea81ffcf7acc5…

MALICIOUS

PDF

88.4 KB Created: 2021-09-20 03:12:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: bb6d89ef8d3fac8c8552404e7b5b319a SHA-1: c4ea6d987ad007d68a57b30e5efb706f35c2dad4 SHA-256: 7b9ea81ffcf7acc5b624f446f8b3c941ae20e231603da9faf02a697993864460
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, many of which point to disposable domains and appear to be part of a link farm, suggesting a phishing or redirection scheme. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicates a tactic to obscure the true destination or distribute malicious content through a chain of redirects.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://comfort8889.com/upload/files/nanifeno.pdf In PDF document text
    • http://primethailand.com/ckfinder/userfiles/files/94900464266.pdfIn PDF document text
    • http://dentalcenterstudio.it/userfiles/files/85304376813.pdfIn PDF document text
    • https://northwestconvention.cz/data/files/dexumo.pdfIn PDF document text
    • https://network-italia.it/file/wuvejitovajime.pdfIn PDF document text
    • http://sporteambiente.it/ckfinder/userfiles/files/wumovozemakasa.pdfIn PDF document text
    • https://www.aukuras.org/ckfinder/userfiles/files/fiwerimovu.pdfIn PDF document text
    • http://khaskhaan.mn/uploads/userfiles/files/motatufim.pdfIn PDF document text
    • http://naturenhuman.com/app/webroot/userfiles/file/nigezujebize.pdfIn PDF document text
    • https://ntc-container.com/upload/files/10483586942.pdfIn PDF document text
    • https://clubkdo.fr/img/pics/files/64899366708.pdfIn PDF document text
    • http://bephoangdung.vn/uploads/ckfinder/files/40642995426.pdfIn PDF document text
    • http://caramelitos.sk/files/56284244517.pdfIn PDF document text
    • https://rubfila.in/files/file/37276942904.pdfIn PDF document text
    • http://tahi.hu/ckfinder/userfiles/files/kuxuzunamufazeba.pdfIn PDF document text
    • https://halkapsikoloji.com/userfiles/file/dezekisidezizifomut.pdfIn PDF document text
    • http://verzorgingsindex.nl/images/uploads/2976963118.pdfIn PDF document text
    • https://szemvidito.hu/sfwkr/feltoltesek/Images/Image/luzuvolazulis.pdfIn PDF document text
    • http://www.farmaciapenil.es/userfiles/files/52010339854.pdfIn PDF document text
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/ef3abf89ef15829dacd9bded5415555b/11737621031.pdfIn PDF document text
    • http://rw-hse-businessconsulting.de/userfiles/file/lilozisatij.pdfIn PDF document text
    • http://kramor.bg/userfiles/file/livufirimemulepu.pdfIn PDF document text
    • https://bdblue.com/ckfinder/userfiles/files/57030921309.pdfIn PDF document text
    • https://remont-bez-zabot.ru/files/file/81241805223.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=playstation+2+games+for+androidPDF 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_off0000f769.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF769 10932 bytes
SHA-256: 62af3418414f0fcebcceb7b46854b6b0a8c1ecd6163dff2ddcfc5ef9b7d7f984
font_01_sfnt_off000110a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110A2 16532 bytes
SHA-256: 166eff7054b2d0bba7fe486a7165cb078677dee6ec1d727782402427977c1dc2
font_02_sfnt_off00013b9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B9D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1