Malicious PDF — malware analysis report

Static analysis result for SHA-256 d2c5dfa780357558…

MALICIOUS

PDF

75.2 KB Created: 2021-06-11 20:28:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: f0e84a414c939b0e192b632490feec9f SHA-1: b288aef204f51c3d4151e4df12f50397890ac57b SHA-256: d2c5dfa780357558c113afd1f147bc5d3ea5728cd8400ddf159643cec92831a0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by ClamAV as a phishing trojan and ML classifier. It contains numerous links to external websites, many hosted on compromised CMS platforms, suggesting a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, contains metadata indicating it was generated by wkhtmltopdf, a tool often used to create documents for phishing lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://infrive.ru/uplcv?utm_term=income+statement+under+marginal+costing PDF link annotation
    • https://tuabogadoangel.com/wp-content/plugins/super-forms/uploads/php/files/a5e4eaf80bfd2f99c1690ce580d913da/nupixinopejavotubu.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1607fd441f1814---xesofutosedosuraxaroxibo.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/697200539d9153289f9281a29a254aff/65699537540.pdfIn PDF document text
    • http://phuwangnam.com/user_file/file/12880132313.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/so2eu31gko23c5c6i8fingsvi4/84618971426.pdfIn PDF document text
    • https://alsterparkett.de/wp-content/plugins/super-forms/uploads/php/files/mlsng0ltbq55uut9v0a33l2vai/zaxuketotinunefakurinos.pdfIn PDF document text
    • https://akproauto.com/nbloom/fckuploads/file/18077907500.pdfIn PDF document text
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/ae09d01225f469262e3a49e9e513a696/88638932201.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094a04a7a90e---sadito.pdfIn PDF document text
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/oqbs6jhuucpvldta32q8nait46/39482058245.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/dfae07f4dc3a8f43e2855d6664dc1c2f/sizolojineloto.pdfIn PDF document text
    • http://isgsrl.it/images/file/37217085635.pdfIn PDF document text
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/8b203d27cf0104717ec4e82987fa0782/37240917401.pdfIn PDF document text
    • http://eia-edu.com/userfiles/file/51180187323.pdfIn PDF document text
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/70baa76b3ddf1052bf756080b3cf3965/6514540767.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e8c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8C4 5196 bytes
SHA-256: ad06e0d37ccef3ef190c618beb76ff602966d749c0196f95b65c3788f96823b9
font_01_sfnt_off0000fa56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA56 10828 bytes
SHA-256: ef8291a9f355bfcdd803e117e1006ec3ea9b1cff908cea903b2db92523a17d9c