Malicious PDF — malware analysis report

Static analysis result for SHA-256 548f57a4b8d7a4f9…

MALICIOUS

PDF

89.9 KB Created: 2021-07-02 19:08:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cbdef58a163f349b449b8b977432ce8d SHA-1: 17653b63a268a4ee3ea86ba71d79b8272c8e1744 SHA-256: 548f57a4b8d7a4f977a2cc5c2198edd3aa33b4b8710f8f92349ed74dfa7f4ecd
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains a link farm with numerous URLs hosted on various domains, many of which appear to be compromised or disposable. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using such links, likely to distribute malicious content or conduct phishing attacks. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9946

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://candica.pl/ckfinder/userfiles/files/piwanura.pdf
    • https://ksboutlet.com/file/files/78547757946.pdf
    • http://anhuizhkj.com/upload_fck/file/2021-5-18/20210518175150124797.pdf
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ca5536b2097---40985698733.pdf
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ac21630175---fukuri.pdf
    • https://whiteelephant.co.in/wp-content/plugins/super-forms/uploads/php/files/338c67d10d6ac0e0e7bc6d728cba4a9f/15755671723.pdf
    • https://www.kasekimi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce442ca2be---35524466030.pdf
    • https://pypconsultores.mx/userfiles/file/1744117271.pdf
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607517fe9ca07---gaposodiwututute.pdf
    • https://space1500.com/wp-content/plugins/super-forms/uploads/php/files/f41d756f21413d84f13b96104e9dab95/vunelafuna.pdf
    • http://emons-verlag.net/testarea/cwsCMSlight/media/files/bejiwewuxivolunozel.pdf
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/7a1da727d061bcd9bf20388d365a3b41/62034361422.pdf
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/qnk0qnf31udobmghqu23cr52us/fizaxenagokubazimerefofid.pdf
    • https://detectiveoffice.net/userfiles/file/83043057041.pdf
    • http://ats-dz.com/userfiles/file/mofebodefod.pdf
    • http://marcth.pl/media/fck/file/bivubibokonalur.pdf
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084536cf006d---wuzokomebife.pdf
    • https://www.oneirishrover.com/wp-content/plugins/super-forms/uploads/php/files/cbfb8dc8e3517270fe4dc3b233effe98/vekumexuborapodir.pdf
    • http://wenxuezj.com/images/File/jekixetikavitidofa.pdf
    • http://thegreenlegacykeepers.com/clients/e/e8/e8dc17949b7ef813e9937e453902477f/File/97736020849.pdf
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/b9c83aa2426f89daa5d2e7b13c071f31/pikotapozuranodusajaf.pdf
    • http://polipadel.com/userfiles/file/pemukanufagugodexelu.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=enpro+poultry+feed+price
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e804.bin
92097b944cc87f86338fe6be646500dbfb8c3b52d3725d56b81c700a1d9ae24a
pdf-font-stream PDF embedded font (sfnt) at offset 0xE804 17272 bytes
font_01_sfnt_off000114bb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x114BB 16792 bytes
font_02_sfnt_off00012cd2.bin
032f51b48a376210041e8d2ba7a5d73dc24a7e6ff3039bd172e42820d374945e
pdf-font-stream PDF embedded font (sfnt) at offset 0x12CD2 10480 bytes
font_03_sfnt_off000144bc.bin
9d5144547e0b729630886a3ad3ce48e7da84b0115899dd9c2390406af6f0fecd
pdf-font-stream PDF embedded font (sfnt) at offset 0x144BC 16092 bytes