Malicious PDF — malware analysis report

Static analysis result for SHA-256 90bcd4bac2c4a3b5…

MALICIOUS

PDF

79.7 KB Created: 2021-09-17 23:23:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 95348e8f43e774355581d4e70a4d0d87 SHA-1: 56abe2e6302e30e397e35d4e2d7cbe454b6dd690 SHA-256: 90bcd4bac2c4a3b586eb1f3461b5b70feb87d14e404798567c5c92c949cc77d5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of embedded URLs, many of which point to disposable hosting, indicating a link farm designed to redirect users. While no scripts were explicitly extracted, the PDF structure and numerous external links suggest an attempt to lead the user to a malicious site, likely for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://biocoop.legreniervert.fr/ckfinder/userfiles/files/tabuvapugo.pdf In PDF document text
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/j2e74tlpb7tdmjmvoqksul2v7k/95887960598.pdfIn PDF document text
    • http://johnlillylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gizigavomidasuduzosamuzu.pdfIn PDF document text
    • http://m-camper.ru/ckfinder/userfiles/files/zukabinorixukosoxuz.pdfIn PDF document text
    • http://www.sictombbi.fr/ckfinder/userfiles/files/norisixopufada.pdfIn PDF document text
    • http://vandientuchinhhang.com/upload/files/xugovimimab.pdfIn PDF document text
    • http://onlinevay.com/upload/files/poralinumulivekugog.pdfIn PDF document text
    • http://kodemari.info/data/files/34630451578.pdfIn PDF document text
    • http://mskgroup-spb.ru/upload/file/62998184100.pdfIn PDF document text
    • http://bagiez.com/userfiles/file/63386147204.pdfIn PDF document text
    • https://bunianco.com/other_files/File/26302449858.pdfIn PDF document text
    • https://investmentskillsgroup.com/images/userfiles/file/28439434817.pdfIn PDF document text
    • https://pakistanchristiancongress.org/userfiles/file/jazotive.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613920b46acfc---dakunexo.pdfIn PDF document text
    • http://www.prieteniitehnicii.ro/documente/file/53671689126.pdfIn PDF document text
    • http://francescofesta.it/userfiles/files/86221830729.pdfIn PDF document text
    • https://agros.net/uploads/file/zukegavusanipowu.pdfIn PDF document text
    • http://pneusmarene.it/images/file/zuwisebodapebep.pdfIn PDF document text
    • http://cgmorenanews.com.br/ckfinder/userfiles/files/5371575290.pdfIn PDF document text
    • https://rajnnuhiddje.se/userfiles/file/66234126651.pdfIn PDF document text
    • http://m3hotels.com/userfiles/file/14784535444.pdfIn PDF document text
    • https://kalendarz.probik.pl/fckeditor/userfiles/file/95700744148.pdfIn PDF document text
    • https://vroa.pl/chplusfiles/file/telixovez.pdfIn PDF document text
    • https://3drm.bg/uploads/pictures/files/58977942297.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=firestick+iptv+subscriptionPDF 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_off0000d51d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD51D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ed2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED2F 17056 bytes
SHA-256: 0e7382cecd4c3c8d73b3bc08b9fb4014030993b63d3bdd2c788c9f9c87435460
font_02_sfnt_off00011977.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11977 10536 bytes
SHA-256: e7477cba3dbae3bf625f154e581bd78de38fc92265b3291f32031bdecee045c8