Malicious PDF — malware analysis report

Static analysis result for SHA-256 41c7a953f0c46b33…

MALICIOUS

PDF

77.4 KB Created: 2021-07-02 16:12:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 56a4b431145dd06bd0aa23730925c485 SHA-1: 0eeb5a7688f031613ba7c822b055e0b90b398de7 SHA-256: 41c7a953f0c46b33bd8591ddd6bd5d10706fa1890abfe26474736f38156224a7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm pointing to numerous compromised WordPress sites, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is heavily obfuscated and appears to be junk data, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8fa434e8dd---4514255980.pdf
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ba3f2a29d4---pafadakibumibibufefefam.pdf
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607aed98e0996---vujadowupo.pdf
    • http://www.orarestauratorisaf.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607c84446e043---bugovaregima.pdf
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/q52h7bgge2mkvj1sfktpt84j9q/kobilisuko.pdf
    • http://alliusie.com/userfiles/file/60910730911.pdf
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/51b3ed872ef96dd64e25b96e3f9edd3b/2172336857.pdf
    • https://bywuf.org/upload/editor/files/korovujodokunowiwibijas.pdf
    • https://www.alphaveneers.com/wp-content/plugins/super-forms/uploads/php/files/324043051019cbe6472d19e3bcda81a9/70306671064.pdf
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16097e0c0af1b4---poriwuvusawezelanadolavas.pdf
    • https://gbagencement.fr/uploads/file/1013050666.pdf
    • http://www.lauricedale.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160999ebaa6a7b---29681568655.pdf
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/7cc985fbc5857b6ae21a554e16ade711/xewunibowuzanimanilef.pdf
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160806a88a8b60---57195455733.pdf
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a013a622ceb---timufogarijivefib.pdf
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160879fdfa9f64---mekukemowerufegupazosufix.pdf
    • https://erdemlerkoleji.com/resimler/files/doguroz.pdf
    • https://mosconi.net/userfiles/file/95051550467.pdf
    • https://thegioidongphuc.net/ckfinder/userfiles/files/42194339576.pdf
    • http://learningkey.org/userfiles/rotezuzux.pdf
    • https://fzclicks.com/demo/files/editor/file/zafajavug.pdf
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/160de2e5c58f86---taguf.pdf
    • https://bodegoncriollo.com/userfiles/file/38749397247.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=sudoku+6x6+with+answers
    • 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_off0000cb86.bin
c0c04875102f68bad81db9d451dacc36b4ed547f0871b38b32ed323e53c7bd8a
pdf-font-stream PDF embedded font (sfnt) at offset 0xCB86 16268 bytes
font_01_sfnt_off0000f585.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF585 16792 bytes
font_02_sfnt_off00010d9c.bin
5b8291b7f04706e84e616097482f8da5672d4e490dbe89c982cc17ab3ae4ffd8
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D9C 10924 bytes