Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e17087fd9846939…

MALICIOUS

PDF

81.7 KB Created: 2021-06-18 10:34:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 09a59e44331673938f84690568b9f68e SHA-1: 6be72c78ab543362bc218a818af6270e1c532c2b SHA-256: 4e17087fd9846939bbef71af5541d9fb1e38e6a457b6e1455a0dc4d6e67529a2
96 Risk Score

Malware Insights

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

This PDF document contains numerous links to external resources, many of which are hosted on compromised WordPress sites. The ML classifier strongly indicates maliciousness, and the link farm structure suggests an attempt to distribute further malicious content. The document body, though heavily obfuscated, appears to be a lure for a workout plan, likely to trick users into downloading the linked PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d89e9ccc53---wizaparozopumegamirunuma.pdf In PDF document text
    • https://www.schroedersales.com/wp-content/plugins/super-forms/uploads/php/files/ef69187abf597240082fd866eb550ffb/47207427115.pdfIn PDF document text
    • http://chinocorporatechallenge.com/clients/6216/File/weburazalajafevemi.pdfIn PDF document text
    • https://windsbs.biz/files/file/vedatobotiwitalamas.pdfIn PDF document text
    • https://www.varishastalari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f94e1c62fc---xivebalutubowofesitujamep.pdfIn PDF document text
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/2h96k9s56e192svm0tm0qv3h2m/dusemotofarotiribopekawi.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16079eac46cee7---voduxusimilivinolotebek.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609843580cf5d---44078548403.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c8b51c0c83e---67102087099.pdfIn PDF document text
    • http://lushexperiences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a576231a83c---melose.pdfIn PDF document text
    • http://wypelnienia.kratex.pl/wp-content/plugins/super-forms/uploads/php/files/117bf71665b67dd941c943ba64b74c15/banup.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/86vm2t01gkg36g93i5u0571jhe/dokifokenorolazuwilova.pdfIn PDF document text
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7b37f63796---gudadu.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160984da41314f---jomevexunes.pdfIn PDF document text
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/1lt1k5aerd688ia3hvj26hr4a3/niruvofagu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=hardgainers+workout+planPDF link annotation
    • 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_off00010196.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10196 5244 bytes
SHA-256: 5b054951a1636fa103b48cfb4b904549cafe5ec13a1336c60a99c8e56e4c97a4
font_01_sfnt_off00011390.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11390 11440 bytes
SHA-256: edf6eea4d68fb067f216be28d680e1fbc1ed5f1704e6c35de8c9f54e8dc353e9