Malicious PDF — malware analysis report

Static analysis result for SHA-256 51a12f18f48ce696…

MALICIOUS

PDF

80.8 KB Created: 2021-09-19 15:43:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 35fb75a18964e654663f0b6861ac62e4 SHA-1: c5c2c815254db2002744331bd775f1b99ca21788 SHA-256: 51a12f18f48ce696f8d95649a096f0de00be4b3ec7df54f0a27e851b5416c2e0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, suggesting a link farm designed to redirect users. The presence of 'utm_term' in one URL indicates a phishing or SEO-based lure. ClamAV detection and ML classification confirm the malicious nature of the PDF, likely serving as a delivery mechanism for further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://crysiq.ru/uplcv?utm_term=credit+card+generator+with+cvv+and+zip+code PDF link annotation
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145f230b4096---42258216136.pdfIn PDF document text
    • https://mimpiindah2.com/contents/files/23063805708.pdfIn PDF document text
    • https://kratky.eu/files/file/55185416212.pdfIn PDF document text
    • https://webmenuplus.com/images/file/baziro.pdfIn PDF document text
    • http://hengtongblower.com/d/files/73578343796.pdfIn PDF document text
    • https://indiantiffin4me.com/nbloom/fckuploads/file/zevafip.pdfIn PDF document text
    • https://mylin.in/ckeditor/ckfinder/userfiles/files/musebajowilile.pdfIn PDF document text
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/t7sn7jmsu7hqt4pdhthj3kugn4/41940798175.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/161426de4a2d65---xozazutewiruxaravogojalar.pdfIn PDF document text
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/u8477imt8ge9ekt0f0o6crbka2/76195259999.pdfIn PDF document text
    • http://acutecardio.ru/sadm_files/vumupanuwigijikobu.pdfIn PDF document text
    • http://maroba-zirndorf.de/file/ronebusevutovove.pdfIn PDF document text
    • http://sibmaxi.ru/userfiles/file/pobitik.pdfIn PDF document text
    • http://maryalo.com/userData/board/file/nividutofiwoza.pdfIn PDF document text
    • http://residenzaeden-albisola.com/userfiles/files/tuzusipo.pdfIn PDF document text
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/161333d352ae59---tijawiraboxet.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614197c559b67---sumusumusugeto.pdfIn PDF document text
    • http://irk-yoga.ru/upload/files/linogov.pdfIn PDF document text
    • http://mail-ex.net/userfiles/file/jalimimadazaselugagivexe.pdfIn PDF document text
    • https://adikkedua.com/contents/files/6588158858.pdfIn PDF document text
    • https://audreyheselmans.com/_files/file/kizufutovoxu.pdfIn PDF document text
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/57e93a6d1f87ca07fc391ad151c4fc20/ziwudirebisuzexudog.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_off0000d6c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eee0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEE0 10824 bytes
SHA-256: 1e3cc1f632668b0ee11e5f9004daf830fad5d9be83a9db454ad95f614d9ad282
font_02_sfnt_off000107ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107AE 17656 bytes
SHA-256: 1af8b3dc94772e19ea6c2a51f300f63f8e569be7d3c34e1f4aaeebb26e71e8fa