Malicious PDF — malware analysis report

Static analysis result for SHA-256 35e0f226bd8830d3…

MALICIOUS

PDF

86.7 KB Created: 2021-07-13 07:21:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7ccd0dcc14cc69e7e15bc04408b1a5ca SHA-1: 17a597bbdcd3468e47fc50c62c4af5441922b827 SHA-256: 35e0f226bd8830d3b03b87443c2c4f0f42c31091894f78ea6816ad68c30c5d78
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and ML classifiers indicated a high probability of maliciousness. It contains numerous links to external PDFs hosted on compromised websites, suggesting a phishing or malware distribution scheme. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct textual clues about its intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://harrisitalia.it/uploads/file/5813464505.pdf
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1608427b8c5401---wetupamuraral.pdf
    • http://fanti-fitness.pl/uploads/assets/file/93751683791.pdf
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/160753b2667730---wirubitozumijij.pdf
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/160b91f8c55bac---lerub.pdf
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fc13137453---zuvefusewopawujug.pdf
    • http://gavinlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/sowifekodirabowiwepume.pdf
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608896e442344---jumux.pdf
    • http://mulroyenvironmental.ie/userfiles/file/21400649525.pdf
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c13a0219fe---silosifofepadodibenela.pdf
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160aae72bbe4ac---waxare.pdf
    • http://www.prieteniitehnicii.ro/documente/file/vomej.pdf
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/6765640821871f99bff8e51d24140afa/jofiji.pdf
    • http://cngwalk.com/fckeditor/userfiles/image/46576161508.pdf
    • http://krzysztofmalec.pl/gfx/fck/file/subabigujepone.pdf
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/160e13679e2f5b---21726756165.pdf
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160856e70f267f---wulon.pdf
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/43b1f229d5cdb25cd089aa8b6569e336/felokurasewa.pdf
    • https://oiweld.com/wp-content/plugins/super-forms/uploads/php/files/ab8566358b13bd0eb6137dfe2f962e6c/pixolipide.pdf
    • https://orrizon.ru/images/file/64045650188.pdf
    • http://brooklinehs1964.com/clients/6/6a/6a3559cec3eb17f551da2d864c8c85ab/File/xegagozagirigufiza.pdf
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/16087978014cdd---99602090337.pdf
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/59e74a2a5e6b0f74f2b9a4963b8d3fa9/bagipazukoroxasifetif.pdf
    • https://www.brightfieldbusinesshub.co.uk/wp-content/plugins/super-forms/uploads/php/files/pfju558bj9fvbtvl5rlpp36cil/bupigifixu.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=project+initiation+phase+deliverables
    • 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_off0000ee0c.bin
012184be52840bebcc5d0556c08403a7d36b8640c381d709abc9431c2bdfd2f2
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE0C 10948 bytes
font_01_sfnt_off00010717.bin
bfe06085565d4bc61000c3e557eab445b972b37a8513a6f6d8c992e689d60e4e
pdf-font-stream PDF embedded font (sfnt) at offset 0x10717 17588 bytes
font_02_sfnt_off00013521.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13521 16792 bytes