Malicious PDF — malware analysis report

Static analysis result for SHA-256 c0b91d871029b475…

MALICIOUS

PDF

72.4 KB Created: 2021-06-27 17:20:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f823ace555131aded4d93788658cda16 SHA-1: 73424688c5dbb26ca5dd756257276409b77ce01c SHA-256: c0b91d871029b4754c7c1599b683c263bb6066ced477b1104d7cfd4b6fce194f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress upload directories, acting as a link farm to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest an attempt to exploit users via these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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 http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160883f57b577b---wimowusofibotebonezuruxep.pdf
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/1487dae708713a49777cbe57c84ee969/62609270938.pdf
    • https://doanhnghiepvietnam.org/img_duhoc/files/memavegazelu.pdf
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160d24771d2cf1---8974390053.pdf
    • https://sluganarodu.org/userfiles/files/dixirides.pdf
    • http://anandamsanyal.com/userfiles/file/sixibexom.pdf
    • http://peaceinsrilanka.lk/userfiles/file/6858249070.pdf
    • http://au-coeur-du-temps.com/userfiles/file/23234522672.pdf
    • http://efuturesthai.com/uploads/files/12232173843.pdf
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/qasbdefs2ab02um0den4bdq2o1/47379456935.pdf
    • http://gesundezellen.de/neu/userfiles/file/jolalubarezizenut.pdf
    • http://ledson.ru/upload_picture/7221592053.pdf
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/fc7353671c715383b62c22c017d56bb2/linuwupid.pdf
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/0a1fe279bedcfd32f8a4a3d9b4518ae8/wotisiremufasuvujif.pdf
    • http://kasargod.net/uploads/file/98471142942.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160826d1abfbff---81807400503.pdf
    • https://churchosonline.com/wp-content/plugins/super-forms/uploads/php/files/ac88d4b8ec8c729647de43cc3e6fdeca/39059637979.pdf
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbf43a8b364---41421356485.pdf
    • http://dungcubepgiangtrinh.com/webroot/img/files/tewumowebis.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=what+to+say+when+someone+asks+you+tell+me+about+yourself
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bb1a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBB1A 16792 bytes
font_01_sfnt_off0000d32c.bin
5abb421d108b2faf0efb0a3154c4b31791d517e8c0f9a4746b993e234f512523
pdf-font-stream PDF embedded font (sfnt) at offset 0xD32C 15644 bytes
font_02_sfnt_off0000faf4.bin
ec96cefb26f2a4e58dca2d9f9d19dc4dbd1033d21f2572b21bb7656bb251b832
pdf-font-stream PDF embedded font (sfnt) at offset 0xFAF4 10912 bytes