Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b19de78594832b5…

MALICIOUS

PDF

79.8 KB Created: 2021-09-12 09:05:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8a579f720f3d65d8f7c0f1c1b2c49e85 SHA-1: e1cd11c0c2e9a86c80fef5ee9d5cfa678137a2af SHA-256: 5b19de78594832b50f8695b2eb6911460edb32f7fc9d5d97fc74d833efa74202
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs pointing to a link farm, suggesting a phishing or SEO poisoning campaign. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags this behavior, indicating the PDF's purpose is to redirect users to a network of other PDF files.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 5

  • 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.
  • 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 http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161344fcc10c20---nerubukuworotal.pdf In PDF document text
    • http://www.mustwalge.ee/data/content/files/51337149105.pdfIn PDF document text
    • http://studiotecnicomartani.eu/userfiles/files/xajusodofesava.pdfIn PDF document text
    • https://reviewz.eu/app/webroot/files/userfiles/files/xapanufemurije.pdfIn PDF document text
    • https://evpersoneli.net/ev-personeli/file/22452120777.pdfIn PDF document text
    • https://gemma.lucien-sv.info/uploads/files/613d4d91eaf2f.pdfIn PDF document text
    • http://smartdeal.pl/files/upload/files/zesafejawibepun.pdfIn PDF document text
    • https://serihosting.com/calisma2/files/uploads/zisutelenaripepilemetiv.pdfIn PDF document text
    • https://swift-tw.com/lcc/upload/files/63891838319.pdfIn PDF document text
    • https://hr-serdahel.hu/images/file/xavozenezitifuxupoxopepof.pdfIn PDF document text
    • http://knipia.com/userfiles/file/92732748898.pdfIn PDF document text
    • https://planningpvedh.nl/ckfinder/userfiles/files/futaxelunilejuwexegeg.pdfIn PDF document text
    • http://climtech.com/files/files/94313000074.pdfIn PDF document text
    • https://www.theknowledgeonline.com/files/lib/ckfinder/userfiles/files/46974239475.pdfIn PDF document text
    • http://www.festivalmarrakech.info/wp-content/plugins/formcraft/file-upload/server/content/files/16136e1bc02011---54744765332.pdfIn PDF document text
    • http://vimbark.sk/editor_uploads/files/tonesosoxis.pdfIn PDF document text
    • https://europacreativaeuskadi.eu/files/galeria/files/pilowovodajo.pdfIn PDF document text
    • http://euroambulans.pl/userfiles/file/571594408.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/21707566109.pdfIn PDF document text
    • http://fertilityupdates.com/userfiles/files/42514539493.pdfIn PDF document text
    • https://svingenieria.cl/userfiles/file/xexoxilukar.pdfIn PDF document text
    • https://domilot.com/uploader/files/27458350433.pdfIn PDF document text
    • https://anna-bel.com/app/webroot/files/userfiles/files/74843092561.pdfIn PDF document text
    • https://gencerenerji.com/resimler/files/68325435474.pdfIn PDF document text
    • https://hgb.se/filer/file/50645518877.pdfIn PDF document text
    • http://ahzycw.com/upload_fck/file/2021-9-8/20210908140855826375.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=android+vs+iphone+emojiPDF 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_off0000d36a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD36A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eb81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB81 10528 bytes
SHA-256: 805e5aa01fa107ef0317f0d80fd57e59b0b614ceed65cb9957f5a6aca7ba318a
font_02_sfnt_off00010333.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10333 18028 bytes
SHA-256: 10bfd7d9003e35ff1224ff863eb9ca6430a156e54e69c5f9a14b185bb3105144