Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d23453481958e20…

MALICIOUS

PDF

85.8 KB Created: 2021-09-16 14:44:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: db50230c6dbaee14b04a960a3fde8a6d SHA-1: cc5f5bb63a0f728b31cdfaec74b9b993d6c08227 SHA-256: 4d23453481958e20ac5ff66e58e32f72bd5620b75175ba0a09d401b1aa13c900
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable hosting and are structured as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is likely used to facilitate the redirection to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • 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.
  • 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://philabc.ru/uplcv?utm_term=imap+settings+for+android+phone PDF link annotation
    • http://tatnhapkhau.com/ckfinder/userfiles/files/84885095852.pdfIn PDF document text
    • http://ctcinsulator.com/uploads/file/67847427167.pdfIn PDF document text
    • https://hoangphatdanang.com/uploads/image/files/85372486308.pdfIn PDF document text
    • http://ukonlinedirect.com/userfiles/files/kigubenomatu.pdfIn PDF document text
    • http://rockpapersun.com/upload_mce_image/file/40083896124.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f2403a3108---4121272522.pdfIn PDF document text
    • https://testagenda1.myagenda.cz/pictures/editor/files/xiwokoj.pdfIn PDF document text
    • http://bulgankhangai.mn/userfiles/files/65451862557.pdfIn PDF document text
    • http://www.velkoobchod-man.eu/ckfinder/userfiles/files/tokibesamixomaz.pdfIn PDF document text
    • http://thaimassagemodel.com/ckfinder/userfiles/files/56654353296.pdfIn PDF document text
    • http://psn-monolit.ru/img_file/files/74209169842.pdfIn PDF document text
    • https://ccaquebec.com/userupload/files/pulovuriti.pdfIn PDF document text
    • http://www.addvanceo.info/userfiles/files/sanuki.pdfIn PDF document text
    • https://europartner2.pl/uploads/65059355397.pdfIn PDF document text
    • https://mandarinusa.com/userfiles/file/1631094657.pdfIn PDF document text
    • http://laxycoffee.com/upload/files/8204898379.pdfIn PDF document text
    • http://savoie-outils-coupants.com/ckfinder/userfiles/files/64014964745.pdfIn PDF document text
    • http://interwork.sk/userfiles/file/42341009305.pdfIn PDF document text
    • http://rqconsultores.com/userfiles/file/fewurozomega.pdfIn PDF document text
    • http://simkoongschool.com/uploads/editer/files/rorebinezepifogebifu.pdfIn PDF document text
    • http://superlitefan.com/uploads/files/34690381059.pdfIn PDF document text
    • http://retailpark.bg/uploads/wysiwyg/files/83534017822.pdfIn PDF document text
    • https://angel-juicer.com/FileData/ckfinder/files/20210916_096E7AE0DA916F19.pdfIn PDF document text
    • http://dblbtech.com/userfiles/file/sepulemolana.pdfIn PDF document text
    • http://girlstown.org/files/js/ckfinder/userfiles/files/989766475.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_off0000e9e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9E1 17908 bytes
SHA-256: 07fc00d0453211e9002aefd287138561372638d57b777082fe7d2dc6e0cd7058
font_01_sfnt_off000118a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118A0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000130b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130B7 10848 bytes
SHA-256: bbd68dd5344d43302a6ecd0102e91956e857d88badbb5b46cd0bb73cba6a5090