Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f566fbd8ec0c252…

MALICIOUS

PDF

69.9 KB Created: 2021-09-28 12:23:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 0b2cc13ac2814bb75c094f07b09d1796 SHA-1: cac9f58c744db69fda50cf7e5835eced99cbf95d SHA-256: 8f566fbd8ec0c252cdc9e599f65d09ed922cdf3974474d122397d294c8f404b8
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains embedded JavaScript and multiple external URIs, with one specifically disguised as a Windows 10 update link. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to exploit vulnerabilities or redirect users to phishing or malware download sites. The presence of embedded JavaScript suggests an attempt to execute malicious code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://ketchas.ru/uplcv?utm_term=windows+10+update+channels PDF link annotation
    • https://coolingrealestate.com/your-home-cleaner/FCKuploads/file/duzonutekokunesu.pdfIn PDF document text
    • http://dallard.fr/ressource/site-image/files/fitoxudokemogemu.pdfIn PDF document text
    • http://mistral-paints.cz/userfiles/files/gonoro.pdfIn PDF document text
    • https://jmcoverseaspvtltd.com/uploads/files/29012577180.pdfIn PDF document text
    • http://tnslib.net/userfiles/files/54324904237.pdfIn PDF document text
    • http://roocenter.ru/upload/file/20013439055.pdfIn PDF document text
    • https://www.lucaslobker.com/minor/ckfinder/userfiles/files/97137534900.pdfIn PDF document text
    • https://ekoelprom.pl/public/images/editor/file/85603200729.pdfIn PDF document text
    • http://simonhoirup.dk/userfiles/file/76166577190.pdfIn PDF document text
    • http://banghetretruc.com/media/ftp/file/35899184511.pdfIn PDF document text
    • http://alptw.com/images/files/3620101862.pdfIn PDF document text
    • http://www.moyekolodin.com/files/xopez.pdfIn PDF document text
    • https://reitinguok.lt/userfiles/file/67891034912.pdfIn PDF document text
    • https://sunriseinnjasper.com/nbloom/fckuploads/file/gijowu.pdfIn PDF document text
    • http://haai.org/upload/file/jetapopidedaxogedobap.pdfIn PDF document text
    • http://hangzhou.chinatupai.com/web/js/ckfinder/userfiles/files/16066883394.pdfIn PDF document text
    • http://ks-klinika.ru/ckfinder/userfiles/files/tupavovigu.pdfIn PDF document text
    • https://detskeihriska.eu/ckfinder/userfiles/files/pexuwikive.pdfIn PDF document text
    • https://listocrm.com/userfiles/files/nemamivonameritifo.pdfIn PDF document text
    • https://jamisonfurnace.ca/userfiles/files/lilujomepaso.pdfIn PDF document text
    • http://theexplorerthai.com/userfiles/files/jejoragegerodosetosukora.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/266b9cec312b2f1b9dfdb15c9ffdbd58/36818023356.pdfIn PDF document text
    • http://mehmetrasimmutlu.com/icerik/file/sudunapozopererazat.pdfIn PDF document text
    • http://nwhouse.ru/uploads/file/9163879705.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_off0000af37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF37 10864 bytes
SHA-256: e48326df581ecdcd2cac6d236650fe1bb3bf342d96bcd4e392584775241849e4
font_01_sfnt_off0000c855.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC855 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e067.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE067 16320 bytes
SHA-256: fb4d9c7d003403f5fb6b147b33f0527cf6b0dad697b489f45df4f59ead0ea0ae