Malicious PDF — malware analysis report

Static analysis result for SHA-256 848f9a97cba1c182…

MALICIOUS

PDF

69.4 KB Created: 2021-09-28 21:56:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c7c5a679a898afb1ec6aaf19a44f16f8 SHA-1: 4b0da1e615f18df3e2cb00a8860ac44b9db18e69 SHA-256: 848f9a97cba1c18235b10727567704287cdbf8dc326f857c3d0a8871c43042ec
156 Risk Score

Malware Insights

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

The file was identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm. It contains numerous external URIs, with several pointing to compromised CMS upload directories or disposable hosting, suggesting an attempt to lure users to potentially malicious sites. The document body is heavily obfuscated and unreadable, providing no direct content clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

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 http://www.groupementpecheduloir.com/ckfinder/userfiles/files/robosumolegikegukiteve.pdf
    • http://dlshixiang.com.cn/ckfinder/userfiles/files/50339015085.pdf
    • https://kebecelectrique.com/upload/editor/file/31443303558.pdf
    • http://otestmanager.org/club/data/userfiles/file/20210901225436.pdf
    • https://yp05.com/_UploadFile/Images/file/zirojitipolurelufodib.pdf
    • http://gestioniarmatoriali.it/xabesilavazubaw.pdf
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16152a6b291ea9---femasomewogilofaxelil.pdf
    • http://royalrep.com/userfiles/files/sajagutojafalevurux.pdf
    • http://ventexevent.se/uploads/file/famukewipudiveziguwavog.pdf
    • http://goodfortune.hk/UpLoadFile/file///mibapodofebosubenop.pdf
    • http://lasantitosrestaurant.com/userfiles/file/pemovaz.pdf
    • http://shuimotongyuan.com/userfiles/file/76163852167.pdf
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/161401da3a040d---49696346832.pdf
    • http://evaemlak.com/userfiles/file///pofikaruputirokobilep.pdf
    • https://vaynhanh365.net/contents/files/pavuzatujabuxetevo.pdf
    • http://ac-kenigsberg.ru/files/file/90417388141.pdf
    • http://salman-is.com/userfiles/file/zugowus.pdf
    • http://cnzhongkui.com/fckeditor/editor/filemanager/connectors/php/uploads/file/121941477605.pdf
    • http://cn-junsheng.com/upload/file///202192404881892.pdf
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/a7848d8ce72ad92c4b4851b1c3578ffb/89928455292.pdf
    • http://alpinedelhi.com/userfiles/files/1546212166.pdf
    • http://refah4ter.info/basefile/hotelrefah4terir/files/44494188832.pdf
    • http://blossomtour.net/FileData/ckfinder/files/20210908_3B46D0880F3AA55B.pdf
    • http://mathahospital.org/userfiles/file/74794350546.pdf
    • https://pataniforum.com/admin/jquery/ckfinder/userfiles/files/dokiga.pdf
    • https://inoxquochoang.com/app/webroot/files/images/pages/files/7422236117.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=fundamentals+of+philosophy+8th+edition+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_off0000b20b.bin
69fea44729f728e6a78394111d42d3ae7276152e2d975d5ced4a185967ea3e59
pdf-font-stream PDF embedded font (sfnt) at offset 0xB20B 11060 bytes
font_01_sfnt_off0000cb9d.bin
bd38cb4bd1eb749f05c0dd89b2f3cd410f1d7f847a61fcef162e28410212d797
pdf-font-stream PDF embedded font (sfnt) at offset 0xCB9D 14328 bytes
font_02_sfnt_off0000ef77.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF77 16792 bytes