Malicious PDF — malware analysis report

Static analysis result for SHA-256 e7621c27ac60c58e…

MALICIOUS

PDF

85.2 KB Created: 2021-07-07 14:54:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 218c808a31cfb6fa896799cf64028f56 SHA-1: a1d8629b80a6aa4999fc263562f35a3e5a997d1c SHA-256: e7621c27ac60c58ecaaad343e7efea17ceb68151078ba37dc4f0a4301ed246d4
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ClamAV and an ML classifier. It functions as a link farm, containing numerous embedded URLs that point to various domains, many of which appear to be compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using such links for potentially malicious purposes. The presence of multiple links to WordPress upload directories further suggests an attempt to host malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://hondamienbac.vn/userfiles/file/38746556861.pdf
    • http://www.awakohchang.com/image/upload/File/isifoligunixegom.pdf
    • http://qca.ch/userfiles/file/94138054026.pdf
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/791f263d635e962889f6f9da0d61a8b9/89815161604.pdf
    • https://partnyor.az/userfiles/file/89020188619.pdf
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/91000c96187760c793bd35fbb844a325/94981307149.pdf
    • https://jiptv.nl/wp-content/plugins/super-forms/uploads/php/files/rl5s62v1s5415g57hp5jkhmbif/kakupanube.pdf
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/4b987fa8c4f0d5bdfc9def95045d1573/madiwuxexevuraza.pdf
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607252f9b8e0a---34728457392.pdf
    • http://www.molinoag.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9073853dc8---53951468745.pdf
    • http://www.alexgis.com/siteuploads/editorimg/file/nimuxevosolabijavowivekof.pdf
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073ca9b47a3d---zatuwusaj.pdf
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/5e12fcf6dbf588c0fa8170e621dcbb86/56791810978.pdf
    • http://kibbkw.com/uploads/file/59244841883.pdf
    • http://a-mega.ua/images/uploads/file/jotit.pdf
    • https://rosedreamholidayhomes.com/ckfinder/userfiles/files/6039401258.pdf
    • https://space1500.com/wp-content/plugins/super-forms/uploads/php/files/bd9b8bdfcff7e16e5beeb188896d221d/lagezene.pdf
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/7ad6a602512e9b548f02ae36bf96e065/bepoto.pdf
    • http://andlupa.com/userfiles/file/bugusudogasetibepovex.pdf
    • http://munsusa.org/userfiles/file/20210523032603.pdf
    • https://bmw-zona.ru/uploads/file/xugaw.pdf
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6407229555---71921680859.pdf
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/c26419806403ce2ce297377d0ec415d7/59075888512.pdf
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/loqs7ai8firep28bkrkb7k58mn/vedapufasedalatu.pdf
    • http://rencontres-icare.org/userfiles/file/fiduzuxoxa.pdf
    • http://orgue-chantepie.info/FCKeditor/upload/file/bogobegekowewufobil.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=20+of+those+infected+with+hcv
    • 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_off0000ebf6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEBF6 16792 bytes
font_01_sfnt_off00010408.bin
4424fd2bfd4752848190054e66b5bf9af208b6608f7ec6bd763f0b37543a0bcd
pdf-font-stream PDF embedded font (sfnt) at offset 0x10408 16624 bytes
font_02_sfnt_off00012f14.bin
1fc87d34e290587d1286f4dda8c5710425541d906ba318d99eb3753b0d69370a
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F14 10564 bytes