Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d5e4f0f07801d20…

MALICIOUS

PDF

86.3 KB Created: 2021-07-03 16:52:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: fc4b605c44c4f809b26fec624846a2f5 SHA-1: 67ef5823dd0317dce4ea393c01fdba610076e89c SHA-256: 3d5e4f0f07801d205a72dd14768fb354e1b916d230a43d629eaada865a5785e8
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically identified as a phishing trojan. It contains numerous embedded URLs that point to various domains, including those hosted on compromised WordPress sites, suggesting a link farm or redirection scheme. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, lacking clear user-facing content but containing embedded URI references.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 https://archism.ru/uplcv?utm_term=who+is+gwen+stefani+dating PDF link annotation
    • http://gavinlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nokozuxopomojikeregud.pdfIn PDF document text
    • http://www.dj-csnl.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607e00b875100---71362327726.pdfIn PDF document text
    • http://dblbtech.com/userfiles/file/detasawaxobidukimokazu.pdfIn PDF document text
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086c48f572a3---9081140615.pdfIn PDF document text
    • http://backkwang.com/userData/board/file/85320191742.pdfIn PDF document text
    • http://pileshoppen.dk/userfiles/file/14330764303.pdfIn PDF document text
    • https://fajanav.com/aym_image/files/88986679269.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/60299b1c24f2005a44d569d321db0a31/zirozuburidis.pdfIn PDF document text
    • http://mp-journal.com/media/file/15427890628.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e4648eab0f---39880125608.pdfIn PDF document text
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/1b3813c1b261f09b5ba4a88765e6af46/30493320336.pdfIn PDF document text
    • http://macautemple.com/userfiles/file/17129403536.pdfIn PDF document text
    • https://cristalensi.com/public/File/79463531763.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7951316b11---tixuvejudurazisebafiro.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/121139a13fcbb923578cd93188123db2/2845896254.pdfIn PDF document text
    • http://fontanarosaserigrafia.it/userfiles/file/fabapo.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/160821887b2b75---27815817258.pdfIn PDF document text
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160a03f497cecd---97959767918.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160de5e04de4db---33337815891.pdfIn PDF document text
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b87527c2e6---kebawisazupowogezurenija.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/4b967t6n7nq1rvgo49pob8hfq3/5015030515.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/160860ed0a76bc---ruxedisevutumi.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acf33f6375f---42446076441.pdfIn PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/6297a1bea0c8e5d142c643c2d11e49eb/wogegobupatirataxovigoxat.pdfIn PDF document text
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082aa13df148---karewupejejusape.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_off0000eef1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010708.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10708 10564 bytes
SHA-256: e5c9b48a421f8eca552c0814cb661eda8eaff45fc4b2198dfed2b418088f5625
font_02_sfnt_off00011ef6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EF6 17344 bytes
SHA-256: 1d67d3f8eb03115840abc18a1aa5cc22dec13bebb0b0ce343b8a56fbbc464c53