Malicious PDF — malware analysis report

Static analysis result for SHA-256 25231385f5398b45…

MALICIOUS

PDF

72.8 KB Created: 2021-07-03 00:44:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: aadc2a439c49c28d8e93f7c844b7ca04 SHA-1: 6db5fb4f48b61d2eef83efe292697a73b75f2b5e SHA-256: 25231385f5398b459e084a8748e6601bb12c576f651a8210b32ce94d40978437
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm. Several extracted URLs point to compromised WordPress sites, suggesting an attempt to lure users to malicious content. The PDF's structure and the nature of the linked URLs strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/16072f9720cdf7---36835174147.pdf
    • http://okmarin.ru/userfiles/file/daxavukojom.pdf
    • http://asfalon.com/__files/file/xizimibilapusufosoxafefu.pdf
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160a363ef0a31d---vekenizok.pdf
    • http://massageindex.nl/images/uploads/42531946403.pdf
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16080c86d97252---pamalojujukukujo.pdf
    • https://abugfreemind.com/userfiles/file/zalabida.pdf
    • https://smilepath.com.au/wp-content/plugins/super-forms/uploads/php/files/c47387691215e67bd27c02561bb2f575/49332125076.pdf
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d60b35e4c43d96ae5bb7bf817c5ccc32/38696459983.pdf
    • http://merlegdoktor.hu/tmp/43043229722.pdf
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/160906f1679dc5---nugoxedarar.pdf
    • https://termoformat.md/img/files/rebirijaxokaxexuvuj.pdf
    • http://tatugigo.com/ckfinder/userfiles/files/wamijunukuwivutirilibi.pdf
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd3815f1b19---47020089642.pdf
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/160c7b8417ceaf---31859892177.pdf
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16078bb6ad3203---rowomit.pdf
    • https://dienlanhbachkhoa.info/upload/files/muzop.pdf
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/160897c277cd52---rofibelug.pdf
    • http://dambi.pl/userfiles/file/bufinoxaligoxer.pdf
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/vf96nhlqlfubbb1ctnsvt2ast3/tazitefipufosunafiletid.pdf
    • http://summithigh75.com/clients/867147/File/52196934669.pdf
    • https://ev-owners.jp/userfiles//files/rumep.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=principles+of+active+network+synthesis+and+design+pdf
    • 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_off0000b66f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB66F 16792 bytes
font_01_sfnt_off0000ce81.bin
501b5bfb45ece5c51b5a6a69ef012d2372b72c00158df2db9d6055f27d117137
pdf-font-stream PDF embedded font (sfnt) at offset 0xCE81 16872 bytes
font_02_sfnt_off0000f9a3.bin
4e4420404b3b6b55ca6ebc08c4fafab47eba57d92584df198053da200b0838e8
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9A3 11260 bytes