Malicious PDF — malware analysis report

Static analysis result for SHA-256 b2e619412780de31…

MALICIOUS

PDF

81.2 KB Created: 2021-09-16 12:19:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: f5b8287e8f695b216cd0e155324b86b5 SHA-1: 56b627770eb6e703c3a49aaadbadf7bcb4f3bd30 SHA-256: b2e619412780de31dce18b0d6bf11d8058157594c7f4830ba27ead282fbe776c
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many hosted on compromised CMS uploads or disposable domains, suggesting a link farm designed to redirect users to malicious content. The heuristic 'SE_PASSWORD_ARCHIVE_LURE' indicates the document likely provides instructions for accessing a password-protected archive, a common tactic to bypass gateway security. The ML classifier strongly flags this PDF as malicious, supporting the conclusion that it is part of a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 6

  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://krisoc.ru/uplcv?utm_term=sync+icloud+calendar+on+android PDF link annotation
    • https://barrier.exma.cl/ckfinder/userfiles/files/13892457339.pdfIn PDF document text
    • https://viettrungson.com/media/Files/79107806080.pdfIn PDF document text
    • http://www.ezmoving.com/file/78438670314.pdfIn PDF document text
    • https://longhoang.vn/upload/files/vibagisifugu.pdfIn PDF document text
    • https://ubranni.com/uploader/files/kedijit.pdfIn PDF document text
    • https://syteq-pro.com/userfiles/file/16878185337.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/16136a5c0587f6---pelupu.pdfIn PDF document text
    • https://guruamardaspublicschool.com/userfiles/files/74768635572.pdfIn PDF document text
    • http://mosme.org/uploadfile/files/45288291586.pdfIn PDF document text
    • http://papienbanana.com/user_file/file/47204329920.pdfIn PDF document text
    • http://exmar.it/foto_fck/file/sifozugetotudon.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/16142f20a5e3c2---ramobumijib.pdfIn PDF document text
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/b119f3adcd7df4e05177c0935ab1718e/16662168865.pdfIn PDF document text
    • https://nenmongdangquang.com/upload/files/80611216459.pdfIn PDF document text
    • http://uniroll.pl/user_images/file/junebajidununovexeket.pdfIn PDF document text
    • http://ildungrice.com/fileupload/fckeditor/file/vovumusogepogiganekimowej.pdfIn PDF document text
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/cec3c65628efa492fd949031dc5d9a5a/11621824304.pdfIn PDF document text
    • http://fanghsin.com/uploads/files/202109040017592945.pdfIn PDF document text
    • https://loffoxfitness.mvwebsolution.com/userfiles/files/garovezawevosejewerojojok.pdfIn PDF document text
    • https://jss-moms.si/upload/File/dolujaz.pdfIn PDF document text
    • http://viquadro.com/userfiles/files/52065963701.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_off0000d61d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD61D 19140 bytes
SHA-256: 0dea8631e6f11182fd9e1aa1953135e65b5fc3019944a0ed9c757625d60ca978
font_01_sfnt_off00010783.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10783 10388 bytes
SHA-256: 4401137b2783733783cf8c0032377d6a8a465fd6ba4f51a999a7454bd41d32e1
font_02_sfnt_off00011f1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F1E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1