Malicious PDF — malware analysis report

Static analysis result for SHA-256 c6f662cb01374c84…

MALICIOUS

PDF

79.7 KB Created: 2021-07-03 13:31:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5c74ba1d5b12cb07a4220aae8e7d2066 SHA-1: 6b018f5fb7c6fcbbda92374f7e8982d9cdd20856 SHA-256: c6f662cb01374c8469da5e18f980eedd9896cf5bf523fb2439ca6988c5ef04b4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous embedded URLs, many of which point to compromised CMS upload directories, suggesting a link farm designed to obscure the final destination. The presence of these links and the overall structure indicate a phishing or redirection attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092f62bc22a8---kiraketazeviduxo.pdf
    • http://khiconghoixuancong.com/Khicong/admin/userfiles/file/25494389198.pdf
    • http://matchedtubes.de/userfiles/file/pemudukepukizizurogelove.pdf
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081a33d8f5fe---weridavef.pdf
    • https://miaousland.fr/ckfinder/userfiles/files/10300472361.pdf
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1f6b5e6e06---liwivirezofiramemusabep.pdf
    • http://uelzecht.lu/userfiles/files/5405910160.pdf
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/7584015e00fba80e4f024d14f7bfbfc5/97999098355.pdf
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/u3ol4osbibo23rmfeue0qubp75/rijuxoni.pdf
    • http://greatnice.club/updatefiles/file/mozugepagelobegego.pdf
    • http://crocepadrekolbe.it/userfiles/files/61482325073.pdf
    • http://jlm-kg.com/uploads/file/widineraxebadawij.pdf
    • https://lawina-radom.pl/files/file/78504163608.pdf
    • http://mahnomenalumni.com/clients/879209/File/lobudinenitodidu.pdf
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/5126a91b69667c155804ca0daf4b38d2/nalesimukunewaduvuboge.pdf
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a07b656772d---xuwagirobepelenodegewo.pdf
    • http://cuuhoatudong.com/upload/files/93637750491.pdf
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/0n3apa4b8ta3249gdo3238ub15/godegutujawaxijomoju.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608743ccae2fa---47291782785.pdf
    • https://hiampelectric.com/wp-content/plugins/super-forms/uploads/php/files/bcad13ee3fd842971878478fa2f34935/pisetijujeduxezore.pdf
    • http://feach.ie/images/uploads/file/4834822474.pdf
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/ed4e45d7e2a36139853c0f6aa422a215/44641514295.pdf
    • https://mimpishio2.net/contents//files/jutusowesipizutuvogat.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=who+to+contact+or+whom+to+contact
    • 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_off0000d719.bin
fa173b4afaa5cfab3acde7220c8211515ca0464d68a86c0e1cc5af8ad36611b0
pdf-font-stream PDF embedded font (sfnt) at offset 0xD719 10136 bytes
font_01_sfnt_off0000ed9d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xED9D 16792 bytes
font_02_sfnt_off000105af.bin
33ddca8529612169acffd120b85acfb31c37cef69a59f2c975c8abaa4079ff8f
pdf-font-stream PDF embedded font (sfnt) at offset 0x105AF 16408 bytes