Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4528af0357b41d5…

MALICIOUS

PDF

97.5 KB Created: 2021-07-07 12:21:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8904e9a6cd12f42f5fbe6e5b2d344556 SHA-1: 9557c56c55e589b32c5ab68c9b5d59d1a5bfcbba SHA-256: d4528af0357b41d5b49e69a96b43c2056e1f60d340e4225d44eb66b1ed9db9be
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple heuristics indicating it is a link farm hosted on compromised WordPress sites, designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were extracted, the embedded URLs and the nature of the heuristics point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/b16a5938537b6bd945ea763daa223aa5/zulofusedoloxeb.pdf
    • http://niestachow.pl/data/aktualnosci_imgs/file/46939486084.pdf
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/89685839030.pdf
    • https://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/21a901b2ec82437edccb1bb411c47a51/81228650576.pdf
    • https://studio-september.com/wp-content/plugins/super-forms/uploads/php/files/3a3caef0ca888638d47a810bcbff084c/favoxuxikadusodisiwusef.pdf
    • https://playerpress.com/ckfinder/userfiles/files/42060457471.pdf
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/4d11d382331537edc27b2e7aebc1a9db/358632517.pdf
    • http://bertrandetgastineaudesigners.com/userfiles/file/pesudexewisowi.pdf
    • http://consade.com/userfiles/file/sisinolunarenefenakoso.pdf
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b7abd2f20cf---susaduvaranoveki.pdf
    • https://sgdivorcelawyers.com/wp-content/plugins/super-forms/uploads/php/files/a62e2c8c96220d251c63b917949677fd/23367560947.pdf
    • http://www.orhancoskun.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bc4c2a444b---muwoguradirezegejigav.pdf
    • http://ccswcd.com/userfiles/file/54289594327.pdf
    • https://transit-connection.com/userfiles/files/xejirubodozadu.pdf
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160b4c70696d29---40023877301.pdf
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a5a2338643---17982950186.pdf
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/d8a6d6e8ffc4e874dd31f818f4d38cc2/87656017181.pdf
    • https://sf-tfi-pgu.uz/wp-content/plugins/super-forms/uploads/php/files/56195b5bfe7086d482e12d7d415f7607/totizivemarunaz.pdf
    • http://turinhotelcompany.com/userfiles/files/dinosimabepifi.pdf
    • https://www.intermediastudios.com.mx/wp-content/plugins/super-forms/uploads/php/files/741ccff7eb56111295c3ea74b30e7d29/xinifagimiwokekekeba.pdf
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/160b86adf06175---23519382378.pdf
    • http://kaupa.cz/userfiles/file/sibivip.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=impression+series+by+water+right+manual
    • 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_off00011694.bin
eae893db70a5473e22220159277fe9925fb582c19a6287af30399c608bfc3a18
pdf-font-stream PDF embedded font (sfnt) at offset 0x11694 18588 bytes
font_01_sfnt_off000146f4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x146F4 16792 bytes
font_02_sfnt_off00015f0b.bin
7994a647c85bc6afb71512116c02dad05e2d9fd513511a05bbcc1726fd523611
pdf-font-stream PDF embedded font (sfnt) at offset 0x15F0B 11092 bytes